If you have not bought yourself the Nexus One Google Phone yet then please read the quick guide on how to buy it below.
All you need to do is visit google.com/phone and then click the “Get your phone”, which will get the whole purchase process started. You can buy this smartphone without a service plan for $529 USD, you can also buy obtain this device with a T-Mobile US service plan at a discounted price, whatever one you choose both phones are unlocked.
You will have to sign into your Google Account and provide your credit card number/billing address/shipping address, and then you will need to use the Google Checkout to complete the purchase. If your existing Google Account is not associated with Checkout, you will also be asked to sign up for Google Checkout before completing your purchase.
Do you want the Google Nexus One with the T-Mobile service? If you do you will need to have this information to hand: Where you will use the phone, Your Social Security number, your existing mobile phone number (if porting your number from another mobile provider) and Your T-Mobile account number (existing T-Mobile customers only).
A little about the T-Mobile service plan: This plan is called “T-Mobile 500 Even More individual service plan” and features 500 Whenever Minutes, Unlimited T-Mobile to T-Mobile calling, Unlimited nights and weekends, Unlimited web access and Unlimited text. This plan will cost $79.99 per month.
Source:http://www.phonesreview.co.uk