How to delete cookies/cache ? How does this web site still trace me ??

ok, i am talking about stickam.com

I use it to spam comments. First time I did it, I spammed my website#1, without any proxy (big mistake), they blocked my account on there.

Someone told me I can only spam 250 comments per hour or it will trigger their system. So, I made adjustment to less than 250 comments, used proxy this time, and spammed my website#2, this time they blocked me because they said I "according to our records, you were previously banned".

How are they tracking me? I used hidemyass VPN proxy and ccleaner to clear data. I know this website stores a macromedia flash file on ur computer, which i've also deleted. Any idea what I am missing or how to by pass them tracing me? I downloaded flashcookiecleaner not sure if its enough

Somehow you're not 'hiding' your ip very well or possibly using a proxy that was also banned?