12-03-2012 06:06 PM
Hi and Welcome to the Community!
If you have warranty coverage (2 years would be unusual), then all warranty service is conducted by whoever your warranty service provider is. It depends on region -- it could be your original place of purchase, your mobile network provider, or an authorized service center. When you purchased, you should have received documentation detailing exactly what your warranty coverage is as well as how to exercise it.
There also might be some good reading here:
If you are unsure where to start, then the best place would be your documentation and/or your original place of purchase.