I have a Scan Tool made by OTC, called the MindReader. It was only OBDI when I bought it 6 years ago, but I spent another $400 and got a new chip for it, as well as a ton more cables, and it now reads OBDII as well. The best part is that now I can run a live data stream on older OBDI Fords, which wasn't possible before. It's kinda cool watching the input values from all the sensors at the same time, live.
Anyway, my Mindreader is by no means the best, but it's decent. I've got close to $900 into it so far, which is nothing. You, however, can buy a new one for less than $500.
OTC Mindreader
These guys are good. I have done business with them many times.
You will still need a book or two to understand everything, but this is an excellent start.
Take care,
~Chris