As an apology for being a bit delayed, here's three entries at once! Don't expect too much of them, though.

Giant, Death

Death Giants are victims of an ancient curse that granted them great powers but left their souls tethered to the negative energy plane. Their abilities are flavorful, but are they competitive?

Ability scores are what you'd expect of a Huge 23-HD giant: impressive strength, high constitution, charisma, and wisdom, and small boosts to intelligence and dexterity.

Their abilities include the predictable Rock Throwing and Rock Catching (which are of zero use against most Epic monsters), as well as the very interesting Frightful Keening. It's not entirely clear whether this ability is a standard action to activate (after which it continues indefinitely) or whether it takes a standard action to use, but from a careful reading I am going to go with the first interpretation.

In other words, the giant can at-will force all living, non-fear immune beings within 100 feet to make a save or be Panicked (which presumably happens every turn?), and causing them to be Shaken even if they fail the save. That said, a sonic, mind-affecting fear abilities that doesn't work on nonliving stuff is easily protected against, and Panicking foes is strong but not encounter-winning.

The giant's SLAs are 3/day Greater Dispel Magic, Unholy Blight, and Inflict Critical Wounds, as well as 1/day Flame Strike. It's somewhat underwhelming, in my honest opinion.

Finally, there's the four 'Soul' abilities. Steal Soul allows the death giant to kill weak (<15 HP) creatures that are near it and capture the souls of anything that dies next to it. Guardian Souls is a very useful ability that grants Charisma to initiative, Spot, and Listen. Soul Healing allows the death giant to heal from negative energy in most situations, and finally Sold Soul is a flavorful but small disadvantage that doesn't impact LA.

Considering everything, I don't think the death giant is on par with anything above tier 5. -0 LA it is, though a less severe one than in many cases.

Giant, Eldritch

Giants: now with magic. They don't get spellcasting (which would be enough to make them competitive) but instead just get some moderate SLAs (at-will GDM and 3/day Dimension Door are most notable), the ability to use scrolls and wands as a wizard, and a +6 bonus on Will saves. Their chassis might give good ability boosts, but ultimately it's still a big giant that fails to be worth its 25 RHD. -0 LA.

Giant, Sand

15 RHD, Large size, and generally underwhelming stats. Continuous self-only Blur is fun, as are 1/day Meld Into Stone and Statue, but in the end it's not worth the giant amount of RHD. The only competitive thing in this statblock is the sandblaster, which is awesome and should be used wherever DMs allow it. The +4 LA currently assigned is crazy: -0 is the only appropriate value there.