See Randall Stross' NY Times article on the radiation and cancer risks of cell phones. To choose a lower radiation phone the next time you buy check out cellrisk.com. You can look up the the Specific Absorption Rate (SAR) of each cell phone. Avoid phones above 1.5. Some lower absorption phones are below 0.5. Motorola's Android Droid, Droid II, Droid X all have fairly high emissions. Whereas their Samsung competitors Captivate and Fascinate have less than a third the emissions.

Another site, sarvalues.com, also has a lot of radiation emission level data on cell phones. But it shows model numbers, not model names. Either that or it is just missing some very popular models.