I just got done replacing my iPhone screen, which I shattered over the break. The part was $30 on Amazon, as compared to a $130 third party repair, or probably a $200-300 Apple/AT&T repair. Yes, I am feeling pretty satisfied right now. 🙂
There are plenty of good videos and resources out there, so I won’t add my own, but would just like to say—yes, it can be done!