The national do-not-call registry opened today. Register at http://donotcall.gov or call 1-888-382-1222. I registered my home phone but didn't put my cell phone number up. I don't get solicitations on my cell, and I'd rather not post it publicly, even for a good cause.
Of course, by the time this takes effect (Oct. 1), I may have ditched my landline altogether.