I need help in writing a persuasive paper?
http://www.powa.org/ ~~> http://www.powa.org/argumentative-essays
Argumentative and persuasive essays are pretty much the same thing. This is the best website I've found to help you with this particular type of writing.
http://owl.english.purdue.edu/owl/section/1/ ~~> http://owl.english.purdue.edu/owl/resource/724/01/
This is another website that's very good.