As far as checking your actual credit report… +1 to annualcreditreport.com
You’re entitled to 1 free look at your credit report from the three main agencies per year. so what I do is set an annual calendar reminder for each of the three agencies reminding me to get my latest report… then I spread each one out 4 months. Thus I’m checking my credit report 3 times a year and covering all the agencies… So in Feb I’m checking Experian, in June I’m checking Equifax, and then in October I’m checking TransUnion.
Finally, if you’re interested in your credit score… you might also check out creditkarma.com. It’s free and has some interesting information comparing your information against the general public to see how you fare.