Can you provide a little more information?
I assume your posting this using another PC since you state you have no internet connection, correct? Why not use this PC to download and burn another program like AVG anti-virus to disc? Run AVG and Spybot Search & Destroy.
This all started last night, I think I might have a virus on my computer
Ok, what did you do last night before the problems started? Did you install / uninstall anything? Visit any pr0n sites?
Have you tried reinstalling Norton or try doing a system restore?