From my previous repair story of replacing the battery in a bum iPhone I got from a friend, I found out the dock connector was the real issue.
It was really straight forward. The steps were clear and I went through them fairly quickly. When I finally got the part installed I put "everything" back together. (Everything is in quotes because I forgot to reinsert the Home button cable into the socket.) I tried hitting the home button to make sure everything worked. And it wouldn't go Home when I hit the button. I went through the repair steps in my head and suddenly realized I forgot something: the Home button. I took it apart again (with much more confidence and ease), placed the ribbon in the socket, reassembled the iPhone... and voila! - a completely functional iPhone!
I was nervous at first. The guide had a lot steps. And it sounded like I could cripple the iPhone if I pulled too hard on some of the cords/attachments. But don't sweat it. Follow the guide. Keep track of the parts and screws. You'll do great! iFixit ftw!