My daughter dropped her iPod Touch and the screen finally cracked. Decided to try fixing before replacing.
It was EXCRUTIATING. Apple doesn't do any favors to the DIY crowd. I was nervous the whole time that I would break some small part or another. HOWEVER - it was successfully replaced and my daughter has her iPod back. Also, if I press hard on the screen I get some white spots that fade in a few seconds.
Take your time. Don't let frustration take hold. Walk away and come back if you need to. The hardest part is that first connection when installing the new screen. After that everything goes back together pretty well.