Ok it sounds to me like you've got a sneaky spyware program acting as a proxy, and sending you to their pages when you browse. Basically all your browsing goes through them. (that, or it just messes with your search pages.. either way, its gotta go)
Phase 1: Anti-Virus, just incase
-A good free online virus scanner is
Trend Micro PCCillin Housecall. Give it a whirl before you do anything else, as there may be things more serious on your machine than spyware.
Phase 2: Clean out the spyware.
-Download
AdAware
-Download
Spybot Search and Destroy
Both are excellent utilities for cleaning up the scum of the software world off your system. Run SS&D first, then AdAware to pick up what SS&D missed.
Phase 3: Reconfigure your browser
-If you are using MSIE, click Tools -> Internet Options -> Connection -> Lan Settings. Check your Proxy settings. Make sure its not pointing to IP 127.0.0.1 or localhost.
Phase 4: Get smart. Get firewall.
-Download your choice of firewall, if you don't got one already. You mention Norton... if you have their firewall, great.. make sure its configured properly and is actually working. Otherwise, I reccommend
Kerio Personal Firewall - only make sure you get
version 2.1.4, not their newest bloated version, 2.1.5.
Hope this helps
