Best bet is to start reading up on pyrit's googlecode page and the associated blog:
1) pyrit - Project Hosting on Google Code
2) Pyrit
Turns out pyrit's author did not like how network cracking was working, and removed it in the latest SVN build. Still, if you can find an older version, you may hit paydirt.
Now, computers that crack at 100 PMKs/sec are pretty slow. You should be more interested in this as proff-of-concept rather than serious WPA work, in my humble opinion. You are better off dropping some cash to upgrade your GPU to some nVidia or ATI card, and increasing your rate 10x or more.



