You need to open up and check if any of the contact points for the home button are broken. If they are, you will need a new home button. Also, it may have damaged the dock connector so check these out and let me know.
Look at the logic board under a magnifying glass for any marks. Also try doing a hard reset. (Hold Power + Home Button) Does the computer recognize that the iPhone is plugged in? Also, take it to a real repair shop. What people can't figure out what's wrong and they are suppose to get paid for it. Sad.
Gary try this. Remove the battery. Now plug in the AC adapter. With the AC adapter plugged in, slide your battery in. Your phone should turn on. If it does, it means you broke the AP board (which has the power button on it). If it dosn't, then check all connections. You don't need the back cover installed in order to turn the phone on BTW. Try it out plz and let me know.
I replaced the Glass on an HTC HD2 today. It was painful but doable. As soon as I get another one to replace I will make a very detailed guide on how to repair and replace the glass and other parts. If anyone has an HD2 with a broken glass they are willing to ship to me, I can repair it (provided the part or cost of part) and can make a guide as well. Note: When ordering the part you need to be sure you order the digitizer compatible with the T-Mobile version.
You will need to put you logic board into another iPhone first. From there, you can make a backup and figure out what else is wrong. -Look on board for any obvious signs of damage or broken connectors. -Look at dock connector and check for bent pins -Test LCD. LCDs can go blank giving a false sign of the phone appearing off. Does the computer recognize a device is plugged in at all when you connect it to the computer? Was it jail broken?
Are the pins still in tact? If so, then test this assembly into another iPhone. If it dosn't work then it looks like the Home Button needs to be replaced. If it does work, then your Dock Assembly will need to be replaced.