Heres a great source
http://austincollins.com/archive.htm
http://austincollins.com/fex.shtml
The first link is about 135. The second is about flying at Flight Express.
Austin Collins is the Director of training at Flight Express and he posts all the training material you need to pass his class there. I believe he wrote it all and its very easy to understand everything 135. If you go to FLX you need to print it all off and take to class.
Also "Everything Explained for the Commerical Pilot" is the best reference book for flying out there. I think its about 50 dollars but well worth the price.