Hold the stock. Buy the iPad. Apple and the economy will get though this. Selling is what made what happened the other day far worse than it had to be. If you truly want to sell, wait until WWDC. That's when to sell. The Market should get picked up somewhat by then. (Disclaimer: I am not a stock analyst or adviser. These are just personal opinions.)
You should have sold at $270 that is what I did. I would argue that if you have to sell Apple stock at $300 to afford an iPad then you probably can't afford it. Stock market is like gambling you have to know when to cash in.