Hey! Sorry, did not see the description. You can fix it but it will require some soldering. There is an ok video on how to do this here: http://www.youtube.com/watch?v=8iWU-x0ZpAw And you can buy the part here: http://www.amazon.com/Ipod-Touch-Headphone-Audio-Replacement/dp/B00450DDDM ifixit doesn't seem to carry 2nd gen ipod parts. This is a fairly difficult repair and if you have no experience soldering, I would not recommend attempting it.
Phillip is right, you cannot text without a phone number. The 3G has no number since it was transfered to your other device. A work around for your problem is to download a texting app from the app store. This should allow you to text from the 3G to another phone. You will have to be on WiFi though.
You cannot glue them together. Whoever sold you the LCD separate from the glass either did no know what they were talking about or lied to you. You must buy the display assembly as one piece. You can buy the proper part here: iPhone 4 (GSM/AT&T) Screen Update: I just thought I would amend this answer based on some recent research. Here in Boston I met a technician at Warlox Wireless who does in fact purchase his replacement LCDs in two pieces. Apple uses a liquid/solid adhesive mix to attached the glass to the digitizer. It is very possible to do this yourself, just not very easy. Cheers.
The short answer is no. A 2009 macbook (non-unibody) lacks the necessary software components to support multitouch. That being said, it may be possible to hack this capability, but not without the aid of some external files.
Ouroboros is right that a little more information would help. If it sounds like the hard drive is spinning up, then stoping, it's possible your HD is failing. If you hear a startup chime and the screen stays black, connecting the computer to an external monitor will tell you whether or not the display is faulty.