Simple Skill Optimization Question

[Dienekes]

So, a character of mine wants to max out his Gather Information skill. Now I'm not an optimizer by any sense of the word, and all I really know about increasing skills is the very simple stuff like the generic 50 gold item, +2 synergy from Knowledge (local), +2 from being a half-elf (won't be using unfortunately), and of course the Investigator and Skill Focus feats. So any information would be helpful.

[Zaq]

What level are you, and how much are you willing to devote to this (feats, race, gold, etc.)? Do you want all-day-every-day effects only, or are you OK with using spells and the like to bump your scores?

[Dienekes]

Only level 6, Rogue/Warblade human, though ongoing campaign so I'll advance. That much is locked in. Gold and feats are probably the best, but I have no qualms with taking other classes from this point on. I'd prefer all-day affects but using spells is fine.

[Chronos]

Gather Information is one I haven't seen optimized much, but a few things come to mind immediately:

A Circlet of Persuasion gives a bonus to all Cha-based skills.
A level of Marshal (or a cohort or party member) with the Motivate Charisma aura will add the Marshal's Charisma modifier to all allies' Cha-based checks (so, added twice, to the Marshal's own skills).
Of course, there's boosting your Cha score, via Eagle's Splendor or a Cloak of Charisma.
The spells Improvisation (bard) and Guidance of the Avatar (cleric) can both add sizable bonuses to any single skill check. You could UMD scrolls or wands of either (note that most things that boost your Gather Information check will also boost UMD).
(Greater) Heroism will boost all skill rolls, among other things.
The Nymph's Kiss feat will boost all Cha-based skill checks, and saves, and also give you more skill points. Spending a feat to get +2 to a skill isn't usually worth it, but Nymph's Kiss applies to enough things to be an exception.
The Truthseeker Goggles soulmeld (available via a feat, or a dip in Incarnate) will give you +2, and you could eventually boost that to +6 by taking the Bonus Essentia feat.