Tracking cookie files that will not delete - any recommendations on how to remove them?

I try to delete everything in the Temporary Internet Files folder at least once every 24 hours. Within the past month, some one has managed to place Backdoor.ProRAT.K. Trojan files on my hard drive at least four times. Spyware Doctor removed the Backdoor files, but now it fails to recognize that I have tracking cookie files on my hard drive that I have specifically told Spyware Doctor to ALWAYS block. doubleclick, fastclick, specific_click, and 2o7 tracking cookie files are among the 37, then 136 files that I have not been able to get rid of for the the last three to four weeks. Is there anything I can do, short of buying another security program, to get these tracking cookie files off of my hard drive? Please give step by step instructions. I know some one is reading my keystrokes as I'm typing. Thank you ,