I'm particularly interested in templates, but in general can anyone tell me what playable races and usable templates would grant Powerful Build to a creature? I only know of like, one. The Half-Giant race. I remember coming across others but I can't remember what any of them were.
Reasonably sure these are the only ones. Of these, the goliath is by-far the best.1
Bonus: the opposite of Powerful Build, Slight Build, is found only in web enhancement kobolds.
1 Half-giants are quite poor for an LA +1 race; aside from slightly higher-than-normal ability scores, they could easily be an LA +0 race. That said, they qualify for the unreasonably-good LA +0 primordial giant template from Secrets of Xen’drik. Combining these results in a race that is almost sorta-kinda worth LA +1?
The goliath is probably still better, though. Especially since primordial tanks a lot of your melee abilities in order to give you superior spell-like ability use, and Powerful Build isn’t really that useful to someone who uses spell-like abilities much.