Multimedia: Render Farms-Choosing best render farms for 3d animation

Render Farms-Choosing best render farms for 3d animation

We're a group of students who are into creating short 3d animation films.Due to timeline constraints and deadlines of projects we work on;we need to utilise services of a render farm.But we don't know how and where to look for the best service providers to meet our needs.
We use Autodesk Maya version 2009 and heavy uasage of renderings of shaders and mental ray output.
Can someone here help us find any render farm service providers or rentals in India or abroad.And also what are the criteria for choosing a render farm price wise.