I've found understanding how a transmission works helps alot as far as what to do and why it reacts in certain ways so I highly recommend this:
Car Bibles : The Car Transmission Bible page 1 of 2
Absolutely brilliant write up and most importantly it includes some great 3D Models and actual videos of them in motion so it's really not that hard to pick up.
I would recommend avoiding the Automatic Trans section unless you're interested after the first part cause your head may explode in a shower of planetary fragments.