Billy...
Like FB said, it is probably in your cable provider, but there is one thing you *might* can do to help it.
Click "Start", then "Run...", in the dialog box type "cmd" and hit "OK". You will get an old fashioned Command Prompt. At the prompt type the following and hit enter:
ipconfig /flushdns
This will flush your DNS resolver cache and might just fix it. If not, you can call your cable provider and beg/plead with them to flush their DNS....but it is probably not going to work
--T