Okay, maybe one of you guys experienced this problem but I can't buy games off of steam. It gives me an error when I click the "purchase" button after I sign in my paypal and all the other jazz. I don't know what to do!. I tried my debit and another account but it still doesn't work! I don't want to miss the stream sale so hurry!
There has been a popular virus going around similar to a phisher that monitors your Steam account and harvests any of your transaction details including debit card numbers, paypal details, etc. You can normally identify it as some Steam features just do not respond upon interacting with them. Same with installing auto-update patches and the like. This sounds very similar to your situation. I would run a virus scan if you have the appropriate software.
I highly doubt Toast would lie about this. What does he have to gain from that? Jack shit. Running a virus scan or two can't hurt anything. My BF had an error when he bought M&B Warband for my Christmas present the other day and I got an error several times when trying to redeem it, then I waited a few and it worked fine. I think it's probably Steam just being overloaded from people buying stuff for the holidays. Though it could be what Toast mentioned.
If all else fails, send a ticket to the Steam Service or post on the Steam Forum. They tend to have good customer service so they should respond in at least 24 hours.