I have purchased unlocked GSM phones from two good web sources: www.cellhut.com and www.celluloco.com. (Disclaimer: I have no interest or relationship to either site.) Prices are very reasonable on most models and you can choose from hundreds of unlocked phones. As Peter mentioned make sure you choose tri- or quad-band, and both sites let you put in parameters such as those when choosing your phone model.

Live the life less ordinary.