Does anyone know where I can get the Halo 1 pilot available as a player character...

Ooh. Me! Me!

Rip the ai/biped from a10

I've ripped it, I have the .biped, I just can't use it because it just sinks right through the ground, I've tried everything to get it to work but it just won't work, so I really need help.

Do you have collision set up?

I just do what I do with everything else, use an existing collision, I've tried everything to make it work. Gamma told me it was something to do with the pilot needing bones. :/

When I add a collision it just sinks through the floor. :(

Ah, right. You'd need to re-rig it I suppose, imo it wouldn't be worth it, but if you insist import the model into 3ds MAX and follow these instructions: http://hce.halomaps.org/index.cfm?fid=1001

I'm not sure if you can simply use a marine rig or not, you should inquire Gamma further.

Actually, I was going to get the pilot working as an in-game character for my single player map. If you still need the tags when I get them working, I can send them to you.

Likewise, if I get them, Ill send you them.

I tried giving it marine animations, when I place it in game in Sapien, it does the no animation pose (Jesus pose) and sinks through the floor.

Animations are based on the bones of a biped. If a biped has different bones than another, it is unable to use that other's animations. The only animations for the pilot are the cinematic animations which are unsuitable for basic gameplay. You'll have to rig the pilot to marine bones for this to work.

Will have to Xfire me about that one, unless it's simple.