I came across this site, that gives a pretty lengthy list of all of GM's current Recalls, TSB's, and campaign's. You will have to look through the list for your problem, but it does help. You can also go to the main web site and search for a particular vehicle, but you wont be able to read the information. The list is long, but very helpful. I hope this helps out.

http://www.alldata.com/tsb/General-Motors/index-issue.html

K2,
Just wanted to thank you for posting this link,just bought an 06 sierra and one the tsb's hit it right on the head,snapping/popping noise up front when turning. Was really bugging me w/ only 400 miles on truck:D