if you want to add 2D court & get basic of player base editing, read this file :
C:\Program Files\Tennis Elbow 2009\Data\HowToMod.html .
To edit World Tour player outfits, have a look there :topic15-1685.php
For 3D courts, I'll try to add explanation in the future, but it might be too hard for most people anyway.
PS: and no need to PM me for generic question...