Hi Aayush7,
Many GMATers are 'rusty' when it comes to their Quant skills, their Verbal skills or both - so you're not alone. To score at a high level on the GMAT, you have to have strong skills in all of those essential areas though - and that means honing skills that are not specifically "GMAT skills."
For free math practice and help, I recommend that you set up an account at Khan Academy (
www.khanacademy.org). The site is completely free and makes the learning a bit more fun and 'game-like' (as opposed to the dry academic approach taken by most books). While the site is vast, you should limit your studies to basic Arithmetic, Algebra and Geometry. You might find that after spending a little time re-building those skills, your GMAT studies become easier.
Before I can offer you any additional advice for your studies, it would help if you could provide a bit more information on how you've been studying and your goals:
Studies:
1) What study materials have you used so far?
2) On what dates did you take EACH of your CATs/mocks and how did you score on EACH (including the Quant and Verbal Scaled Scores for EACH)?
Goals:
3) When are you planning to apply to Business School?
4) What Schools are you planning to apply to?
GMAT assassins aren't born, they're made,
Rich