List of how to unlock what?

[Gaidren]

I've looked for a guide to how to unlock the various classes/races/talents, but no luck (including the wiki).

I'm sure such a thing exists, but I can't find it.

Also, I recently donated $ but Stone Warden doesn't seem to have unlocked (Exploration mode did, so I know the game registered my donation).

[Crim, The Red Thunder]

For stone warden, make sure you select the dwarf race FIRST, then open the wilder tab, to find stone warden there. (If you don't have wilders unlocked, you'll need to unlock another one first, summoner being the simplest.)

As for how to unlock the unlockables, the spoilers forum has a fair bit on it, though many just come from doing your main storyline/optional quests. A few more come from certain achievements (2 of the skill trees, 2 classes.).

Which one in particular are you trying to unlock? If you just want a catchall list, you should ask in the spoilers forum instead.

[Gaidren]

Thanks for the info on Stone Warden. I'll try that (selecting Dwarf first).

I was curious on the unlocks in general, nothing specific. Per your request I'll post in the spoiler forum.

[Nizidra]

I've looked for a guide to how to unlock the various classes/races/talents, but no luck (including the wiki).

I'm sure such a thing exists, but I can't find it.

Also, I recently donated $ but Stone Warden doesn't seem to have unlocked (Exploration mode did, so I know the game registered my donation).

http://te4.org/wiki/Unlockables <- contains spoilers

I'm not sure how one should look for it and not find, because link to this page is on main page of wiki.