These are really incredible XDF files for TunerPro by dimented24x7!
There are some ADX files around as well. Most from by Jayme from delcohacking.net He has been working on this more so I'm going to link to his thread on DelcoHacking.net so everyone can grab the latest version. He's done a great job and had no idea it would be used this much so sign in over there and give him a thanks for his work!
The only issue yet and a flash cable... but not if you have a RoadRunner from Moates. If not you'll need a cable for OBDII:
And there are two flash programs soon to be released.