Since Vat is under State Government,Rates of Vat,Challan and Return procedure are different from state to state.
However,Basics are same for each state which you can study here
http://www.teachoo.com/subjects/practical-taxation/practical-vat-cst/
However,Challan and Returrn Procedure discussed in Teachoo is only of DVAT
For Other states,you can Download following file