I was browsing through the Warhammer: 40k - Dawn of war mods and each of the best ones is looking for voice actors. No design documents, the intention pretty much starts and ends with a discussion. One of the really important reasons is an absence of competent actors.
When you start a free game/mod, you have to start with coders, artists and designers but you have to end with voice actors. It would be a great improvement if there was some kind of database or site with a list of voice actors, short sound samples and more. The sound guys and musicians have generally the best hardware and software available in the free scene + you don't have to say "Jump on my sword evil, I won't be as merciful!" (BG2) for the acting to become a fun.