I developed ITB Syndrome in 2004 after doing 3 centuries in just 5 weeks. I found some good stretches online. Here are some of them:

http://www.lwcoaching.com/library/runnersguideitbs.htm
http://www.runningtimes.com/rt/articles/?id=6099
http://www.triathloncoach.net/itb_Stretches.htm

You usually hear more about ITB Syndrome in runners, but it can definitely happen to cyclists too. I was instructed to lower my saddle slightly and to avoid hills for a few weeks, as well as long distances. I did that, gradually easing back into riding, and hills, and after about a month, it never gave me another problem. I still do some of the stretches to this day. Googling on "ITB Syndrome" will give you all the information you could ever ask for and more!

Good luck!
Emily