where can i find divx
 

is there some kind of dvix player that i can put on my xbox so i can download movies to it and wacth them

yes, you can play divX movies with Xbox Media Player a.k.a. "xbmp".

where can i find that and how do i install it

Well, I'll pm you where to find it.

As for installation, you just send it to your hard-drive along with the movie file, and add a link to the default.xbe through evolutionX. Or, you can burn it to a dvd/cd-rw with your movie file, and play it like that, but many people have problems with playing off a disk.

not real sure on how to and a link is that like doing the skin folder

On my site, I have a small tutorial on editing the evox.ini file, so you can make a link to your apps/games. If you can get xmbp on your xbox, you can follow that tutorial to make the link.