SL,
Here are some great self-help exercises that you should find beneficial in lessening your anxiety and symptoms/attacks. They are from the Resources that I mentioned above. Practicing them everday can really make a huge difference!
Self Help sites with breathing/relaxation exercises instructions
Panic attack relief exercises:
http://www.healthcentral.com/anxiety/c/73076/34334/breathing-lessons/
http://www.healthyplace.com/
http://www.stress-relief-exercises.com/
http://www.ehow.com/video_4405003_breathing-exercises-panic-attacks.html
http://www.psybersquare.com/anxiety/panic_relax_I
Keep posting!
S.C.