You can find a large F1 Twitter directory as well as a list of GP2 tweeters on F1 Fanatic.
I’d like to contribute to this database by creating and updating a list of WTCC drivers who use Twitter. I plan to update this list when new drivers join the championship or new accounts are created. I probably have missed a couple of drivers so I will be happy about your suggestions and corrections, too.
Current drivers (participating in the 2012 season)
Andrea Barlesi
Fredy Barth
Tom Boardman
Tom Chilton
Tom Coronel
Stefano d’Aste
Pasquale Di Sabatino
Alexey Dudukalo
Robb Holland
Rob Huff
Norbert Michelisz
Fernando Monje
Tiago Monteiro
Yvan Muller
James Nash
Charles Ng
Michel Nykjaer
Pepe Oriola
Darryl O’Young
Colin Turkington
Isaac Tutumlu
Former drivers
Robert Dahlgren
Javier Villa
The official championship twitter account