Where are you from? If you're in the UK then search for 5% crucial discount in google. Corsair ram's also very cheap and highly recommended so have a look around newegg/dabs for that.
Edit: Also as WildCowboy says, Crucial can be slightly arsey about their pricing at times. Try different browsers and once you've found the memory do a search for the generic version of the memory on their site. I have to say though that Crucial RAM has always been the most reliable in all my years of computer use, even if they do fudge the numbers sometimes.