Hit me up with ANY detailing questions you may have. I've worked as a professional detailer and even owned my own mobile car detailing business. Go for the meguiars from wal-mart for now but later pick up a more aggressive kit, for instance:

http://meguiars.com/estore/product_l...ectionID=31201

Number 1 rule is don't drop the clay bar...
Also, don't rub on the car to hard as it will be counter productive. Simply "glide" the clay over the paint and allow it to do its job.

Check out pictures from my myspace page (signature) to see a detail session I did on my car.

 

^^^
+1,000

Even on tile or linolium flooring. It will pick it up and NEVER let it go. So basicly its trash unless you realy dont like them, then just donate the claybar.