The best Steam Punk Gnomes that I've found come from Bluffside: City on the Edge. All the information from that section is open content so I can post it here. I removed the Religion section since it only mentions the new deities from Bluffside, which I'm not sure are open content. I've put it in a spoiler for length.

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Steam Gnomes
For countless centuries, steam gnomes have known only one home—built of rock and darkness far away from the glaring rays of the sun. Here, the steam gnomes (a topsider name) build vast cities and carve out a living turning raw coal and iron ore into tools to power their industrial lives. The Great Sundering revealed the underground realm to those on the surface,
which surprised both sides. The topsiders had no idea any civilization existed beneath the rock, and the steam gnomes were equally shocked since the underground realm was the only one they had ever known.

Personality: Steam gnomes, unlike their surface cousins, are very serious and hardworking. They do not have the gleeful sense of humor of their cousins, and the two groups view each other with disdain for this same reason. Steam gnomes are meticulous in their work, and believe anything worth
building is worth making it last forever. Machinery is the bedrock of civilization, and master artisans hold the greatest respect in steam gnome communities.

Physical Description: Steam gnomes stand about three to three-and-one-half feet tall and weigh 50–55 pounds. While generally the same height as surface
gnomes, they are more muscular. Their skin is soot-black; however, when washed (a rare occurrence), they are fair-skinned and very pale, with a slight bluish tinge. Steam gnomes encountered underground are covered in smoke and ore dust, and are filthy black.

They are smooth-faced, and most are bald or balding. Steam gnomes generally wear strappings of metal armor and always carry around tools. Most also wear hard metal mining helmets, both above and below ground. Steam gnomes encountered on the surface wear special tinted glasses to block out the glaring sun.

Relations: Steam gnomes get along well with most surface races. After the Great Sundering, steam gnomes ventured to the surface. They discovered a wealth of strange ideas and raw materials. Steam gnomes will trade with any race, including those considered evil, if they can get a profit. They are neutral to all surface races, including gnomes, who they view as spoiled
and immature. They have a deep hatred for drow, duergar, and other underground evil races.

Alignment: Steam gnomes are mostly good. Evil steam gnomes are extremely rare, and are ostracized from their communities. Likewise, steam gnomes tend towards neutrality and chaos. Steam gnome cities rarely enforce strict laws, relying on the greater good to adjudicate the will of the people.

Steam Gnome Lands: Steam gnomes live in vast underground communities. These cities all begin in natural caverns, and are filled with architectural and mechanical wonders. Steam gnomes get their name from the steam they use to power their empire.

There are two classes of steam gnome: miners and tinkers. Miners are the majority and are responsible for mining iron ore for building and coal for burning. These industries produce a lot of smoke and water vapor, so their cities are filthy by surface standards. Steam gnomes developed elaborate systems of fans and pipes to funnel smoke into extinct volcanoes. They never thought about where the volcanic fissures led, they were just happy to remove the smoke filling their realm. Lands around these outlets are covered in black soot and gray ash from decades of constant pollution.
After the Great Sundering, steam gnomes discovered a whole world existed
above ground. They can be found anywhere in the world, although they are most common underground. Steam gnomes do not like the sunlight, and if
they go above ground, they prefer to do so at night. If out during the day, steam gnomes wear dark sunglasses to protect their eyes from the light.

Language: The steam gnome language is precise and mathematically-based. It is full of descriptions of rock and mining, as well as technical words for tinkering tools and processes. When the Great Sundering occurred, steam gnome scholars worked feverishly to develop thousands of new words for things they were discovering on the surface. They found it more efficient to learn the common tongue of the surface instead.

Names: Steam gnomes consider names vitally important, as a name indicates a gnome's place in society. Because invention and craftsmanship are revered, steam gnomes want full credit for their work. Steam gnomes names must be completely unique and must fully describe the gnome’s ancestry and accomplishments. Vast libraries run by steam gnome librarians name new additions born to the clans. Over generations, the names have become longer, more complex and intricate. Most are now unpronounceable by
topsiders. Like their gnomish cousins, steam gnomes commonly adopt nicknames for ease, but use their technical names when dealing with members of their own kind. Steam gnome scholars can instantly recognize the age of a legend concerning a steam gnome from his name. A steam gnome with a 12-letter name is hundreds of years older than one with a 14-letter name, for example.

Names: Zyxilvickulnistmort, Manginjolipdsolivor, Abunmiltaflagenviel,
and Hlindronomilikindio. There is no distinction (as far as any topsider can tell) between male and female names. Their overworld peers generally assign steam gnomes nicknames. They lack the desire to come up with a suitable one on their own. If they do, it is usually just as long and unpronounceable
as their real name.

Adventurers: Steam gnome adventurers are scholars, craftsmen, and scientists. Like their topside cousins, they are intensely curious and ambitious. They are constantly looking for ways to improve technology, and dream of one day creating a glorious steam-driven world. Steam gnomes that adventure on the surface are usually wizards, rogues or fighters. All steam gnomes are trained in the art of tinkering. Steam gnome clerics rarely leave
their underground complexes.

Steam Gnome Racial Traits
• +2 Constitution, +2 Intelligence, –2 Wisdom, –2 Charisma: Steam gnomes are tough and resilient, but are serious and unemotional.
• Small: Steam gnomes gain a +1 size bonus to armor class, a +1 size bonus on attack rolls, and a +4 bonus on hide checks. They must use smaller weapons than humans. Their lifting and carrying limits are three-quarters those of Medium-size characters.
• Steam gnome base speed is 20 feet.
• Darkvision: Steam gnomes can see in the dark up to 120 feet. This vision is black and white only, but retains detail.
• +2 racial bonus on all tinkering skill checks. Tinkering is ingrained in steam gnome society and all steam gnomes, regardless of societal function, are trained in it. All steam gnomes, regardless of class, receive tinkering as a class skill.
• Automatic Languages: Steam Gnome and UnderCommon. Bonus languages: Common, Gnome, Goblin, Draconic, Drow, Duergar, and Dwarf. Other languages may be available based on races in the vicinity.
• +2 racial bonus to a craft skill of the player’s choice. Steam gnomes are expert blacksmiths and artisans.
• Stonecunning: Stonecunning grants steam gnomes a +2 racial bonus on checks to notice unusual stonework, such as sliding walls, stonework traps, new construction (even when built to match the old), unsafe stone surfaces, shaky stone ceilings, and the like. Something that isn't stone but that is disguised as stone also counts as unusual stonework. A steam gnome who merely comes within 10 feet of unusual stonework can make a check as
if he were actively searching, and a steam gnome can use the Search skill to find stonework traps as a rogue can. A steam gnome can also intuit depth, sensing his approximate depth underground as naturally as a human can sense which way is up. Steam gnome have a sixth sense about stonework, an innate ability that they get plenty of opportunity to practice and hone in their underground homes.
• Favored Class: Expert (Tinker or Miner) as NPC; Fighter as PC. A multiclass steam gnome’s fighter class does not count when determining whether he suffers an XP penalty.


Debby