Dropped phone screen now unresponsive and white w colorful lines iPhone 3G

Hi everyone --
In the year or so that Ive had my 8G iPhone 3G, Ive accidentally dropped it numerous times. Im terribly clumsy -- this is actually my third iPhone. Anyway, about two months ago, my phone got a series of large cracks across the top piece of glass after being dropped. Then, a days later, I had the phone in my back pocket, sat down on a curb, and cracked the screen even more. Everything on the phone continued to work fine, other than the fact that it was hard to see certain things due to the cracks. This was up until two days ago, when I dropped the phone yet AGAIN, this time 2-3 feet onto a linoleum floor. Immediately, the screen turned white and a series of weird, colorful lines appeared. The only way to stop this problem was to hold both buttons until it finally cut off. When I cut the phone back on, the same things happen.
Ive heard that both screens are now damaged: the top, glass screen and the LCD (?) screen underneath. Basically Im just curious if anyone else has had this experience. What are my options for fixing this? I really dont want to shell out several hundred bucks for a brand new phone, nor do I want to pay Apple $249 or however much it is to have them repair it. Im sure its frowned upon, but a friend of mine ordered a replacement screen and repaired her phone on her own. Feedback? Thanks!