Also the Bentley manual kicks ass and even helps with diagnostics.
Oh and has anyone taught you the stomp diagnostic? You press the pedal 5 times and the check engine light will blink out a code. You then reference this to narrow down what system has the problem. Here's a better explanation http://www.pelicanparts.com/BMW/tech...nostics%20.htm
Pelican and this site http://www.bimmerdiy.com/e30
are pretty good when you don't have a book. They're not perfect but they will get you moving.