Won't Start - I think it's the immobilizer

[imari]

I was on my way home from work, my wife called to say that my alarm (horn/lights) on the Boxster was going off. I don't know what triggered it. When I got home, the alarm was going off so I put the key in and tried to start it but it wouldn't turn over so I took the positive battery cable off to stop the alarm and then put it back on...but now the car won't start. I'm almost certain that it triggered the immobilizer but I don't know how to reset it to get the car to start again. Any advice would be greatly appreciated!!!

Also to note: the lock/unlock buttons on my key fob do not work so it can only be locked manually (not sure if that is a part of the reset process). Thanks again for any advice!