I use the Traditional Medicinals "Women's Moon" tea...love the stuff! I also found that being on very low doses of Paxil cut the cramping tremendously, but I wouldn't recommend it as a first line of defense!
Black Cohosh is another good herbal remedy that reduces inflammation and controls your hormones:
http://nccam.nih.gov/health/blackcohosh/
Also, don't forget to breathe! I started taking yoga classes and being mindful of my breath, and one thing I noticed is that I tend to breathe shallowly with pain. Breathing deeply helps move the pain on through.