When do you need the SIM? The reason that I ask is that I have 2 prepaid sims that are less than a month old and, if you are leaving soon, can be yours. One has the remainder of a 500 baht top-up in it; the other is just a basic that, I think, expires after 1 month without top-up.

The best place to buy your SIM is in Thailand. In Bangkok, they are available on the street for as little as 360 baht (be sure to have the seller activate it), but the best source that I found is the store located in the Siam BTS station (near the exit leading to Siam Square Shopping)-on the right as you exit. They charge 400 baht for a "1-2-Call" card. They speak good English, activate the SIM, and have top-up cards. 1-2-Call is AIS and charges 5 baht/min. domestic and 21 baht/min. international to the U.S. Topping up in Thailand can sometimes be difficult if you do not speak Thai-especially on the street. This method was simple and pain free. I have used the 1-2-call SIM in a large portion of Thailand and it works better than my domestic T-mobile. Areas used include Chiang Rai, Chiang Mai, the Golden Triangle/Myanmar/Lao border, Phuket, Krabi, Surat Thani, Ranong, Hua Hin and Bangkok as well as in between. Much better coverage than one finds in Oregon or Washington.

Note: it does not roam internationally but does throughout Thailand. To call the U.S. use +1 area code number.

E-mail if you need the prepaid SIM.