You didn't mention from which state you are.So I am giving the list in various places.See it and choose which one is near and best suitable for you.The best IIT coaching centers in India are:
Best IIT Coaching centers in Delhi : FIIT JEE, Akash institute, career launcher.
Top IIT Coaching centers in Mumbai : Vidyalankar, IMS learning, career launcher, FIIT JEE , Akash institute.
Best IIT Coaching centers in Kota : Bansal classes, allen career institute, career point, Resonance.
List of IIT Coaching centers in Hyderabad : Bansal classes, allen career institute, career point, Resonance.
IIT Coaching centers in Chennai : Yamuna Coaching Centre, Brilliant Tutorials Private Limited, Anugraham Classes, Ascent Education and Sriram academy.
ALL THE BEST...