I didn't get a MIR form with my TP2 either. I called sprint and they directed me to
www.sprintrebates.com
I found the form, and was surprised to see it say to be eligible, you must have maitained your current device for 22 months. This WAS NOT explained to me, and was the first I've ever heard about it.
My plan is to go to a local Sprint store in the next week or so (they won't give you the rebate until you've been on for 30 days anyways) and pick up a MIR form as opposed to using their form on the internet.
If I get resistance from Sprint on this, I'm not going to be happy!
Cosmo