I bought an HD radio listed on the rebate form previously listed in this thread that does not require a cell phone.
It appears that the telephone number listed, 800-915-2797, for rebate assistance is not correct. That telephone number in the U.S.A. belongs to the SMC corporation. The SMC folks are getting calls on the HD rebate, but they are not a rebate center. Furthermore, this company has not yet received any telephone calls from the folks that are running the rebate offer so that they can refer people to the correct telephone number.
I do not own a cell phone. It looks like one person got a rebate using this form. However, I have not yet received a reply from the HD Alliance about the veracity of this offer. I am a bit nervous about it.