Vin #s & Auto Trany

Does some one have a link or some thing that breaks down the vin#s?

I am looking around for trucks right now and you can't ever trust what the sales guy tells you, would rather look at the vins and see for myself.

Also, what do yall think about the auto tranys on the 03-06s. Have heard alot of complaints about them still. Stuff like them jumping in and out of gear, ect...

Thanks