After a bankruptcy some 6 years ago, I decided to try and fix up my credit since I was getting some crappy interest rates. I stumbled upon - www.creditinfocenter.com
They have a forum to help with the little details, but the main page is the most helpful.
My credit isn't great yet...but over the last 2years I've been able to bring my score up 90-110points and aquired 2 cards that will help with the score being brought up as well.

A couple things I've learned from this site:
1> Credit cards are good as long as your balance is less than 30% used based on the credit line.

2> There are so many laws that can help you fight/sue the credit bureaus, collection agencies and the false info on your account.

3> You don't need someone else to fix your credit (unless you sue-even then maybe not) it is very easy to do, just takes time!