Develop an API ; requests using GET variables via HTTP-requests

I am looking for an integration of the API, so the following functionality will be integrated in my website: automate the creation of new customer accounts. automate adding and removing credit from customer accounts. automate adding phone numbers to customer accounts so they can use local access numbers. automate validation and resetting passwords of customer accounts. automate blocking and unblocking customer accounts. get user info, like balance and current active phone numbers. get call detail records of each customer account An example of what you can build with our API: Your customers can create a user account on your web page. After that they can log on to their account page, see their balance, see call history, modify their phone numbers, buy credits and see their purchases, all this without ever knowing bestvoipreselling or voipinfocenter. Implementing the API gives you great freedom in creating a fully independent web page. How it works: You can send API requests using GET variables via HTTP-requests. e.g.: [login to view URL] [login to view URL] _&password=______&customer=__&customerpassword=___ &geocallcli=__&tariffrate=_ IMPORTANT please include exemples of similar projects you have done