I've bought a 1-2-Call SIM when I first got here a year ago. I don't remember whether I had to show my passport, but nothing else is required in any case. Available just about anywhere where you can get a phone.
My girlfriend has a TrueMove phone and coverage seems a little less than mine.
Even if you only want to receive calls you will have to recharge your account from time to time - if you are staying long time. The credits expire after 30 days and I think you can be called for another period, don't know how long.
Cheers,
Peter.