http://www.shef.ac.uk/international/admissions/india.htm
I came to know that if one has >=70% of marks in English in his XIIth standard then there is no need in taking up any further english language exams. Then there is no need to take up TOEFL is it ?

That's correct, at least for Sheffield University, but you'll need to check the conditions at each university you apply to.

I'm crawling all possible websites including british councils' site. I need to know abt some scheme through which I can get scholarship and stipend for all the 3 yrs (complete duration of PhD). Plz tell me if there is any.

Our media of instruction is english from our Secondary school level to master degree level, either we need some english language course like IELTS or others?