Att...............

 

Welcome to the forum

It would either be compatible with T-mobile (1700/2100) or Att (850/1900) depending on the model you bought. Either one you could just walk into one of their stores and ask to sign up for a plan and get a sim card. Just pop it in and your good to go. I don't have the Att version but I've heard that you can just sign up for the basic $40/mo voice plan and go online to your Att account to add a dumbphone data plan for $15/mo instead of the $30/mo for a smartphone plan. Also... dont let them tie you into a 2 year contract. Make sure it's contract free!

 

I have the tmo version and i can use it with att also, just wont have 3g.

 

If you are getting a prepaid SIM with AT&T (Gophone) you do not need to buy data (though you might want to and you can without a contract). Data is not required if it does not have AT&T branding or ROM (AT&T compatible Nexus One has neither). You simply put money on the SIM. If you accidentally use data, it will just burn up your allotment fast. If you run out of money on the card, that's it. No mystery charges.

 

you also have the option of turning off wireless data as well.

 

Yeah I have a. At&t nexus 1 and originally used a pre paid sim before I setup a non contract plan. you can get really cheap text and talk packages however they will try and rape you with pay as you go internet data which is why I just used wifi. Eventually I hated only having internet connections only at certain places so I went with one of their expensive data plans $60 for 450 minutes and unlimited text and $30 extra for unlimited internet. I got the internet deal right before they killed their unlimited plan