Here are some links to the workshops that I use, and some sites I visit frequently...

Favourite Sites
Ausrotary.com
Real Per4mance
MazdaRotary.Net
HIoctane.com

Favorite Shops
Rotamotive Racing
Wolf EMS
Microtech EFI
Simplymaz
Guru Motorsports
Hitman Injection Tuning
Pac Performance
Horsepower In A Box
Difftechnics