anallawalla - 4:10 am on Sep 23, 2011 (gmt 0)
I am from Australia and have investigated a few things.
I have an unlocked GSM phone that I bring with me. I also bring a $14 Nokia pre-paid phone I bought in the US (whose freqs don't work in AU).
Since I come at least once a year, I bought a T-Mobile SIM for around $25 and $100 worth of credits to get a "Gold" status, which keeps the number alive as long as I recharge it once a year. One of the first things I do in Vegas is to go to the Boulevard Mall (not just for the recharge) and buy $10 worth of credit and apply it. Sometimes I buy another credit to keep in my travel folder, in case I am going somewhere else and wouldn't have time to shop.
The T-Mobile pre-paid has no data included, so lately I am studying discussions in an Aussie forum where there is a lot of info on this. The wisdom of the crowds is to get an AT&T SIM (there are many to choose from) that costs around $11 from entrepreneurs on eBay and elsewhere, then put about 500 MB of data on it. This will let you do a little bit of FB/4SQ etc without worrying. Some people buy a monthly plan with 2 GB data and cancel it after a month. This trip will use my iPhone as a hotspot for my iPad and will use the AT&T SIM for it. I will keep the T-Mobile phone for calls since my regular Pubcon mates have that number.