I dont know about the ones that guy on CL is selling, but you can get those way cheaper on EBAY (which is where he probably got his).
Just go on ebay and google: LED Strip
Look for the waterproof ones, as those strips come sealed in a plastic casing. I actually got 2 strips of blue ones off ebay before and I wired them up as moonlights. REALLY nice.
I think these are the ones I got:
http://cgi.ebay.ca/48-LED-Blue-Flexi...item3f02cf0c10