How do I research a filetype so I can write an import script for it?

[ShadyTheFirst]

I'm currently looking into multiple games that I would like to be able to extract models from, all of which use proprietary formats for their models. I can't find any truly helpful information about this subject. So if anyone could point me in the right direction that'd be great.

[dlight]

Google if extractors already exist. If not you can ask in some forums for tutorials for reversing model formats. As mainly english forum for general extraction i can point you directly at the Xentax forum.