I jumped on Ribble, and put the following in a basket: 4600 crankset (choice of compact or std), 4600 BB, 4600 chain, 4600FD, 4600 RD (short), 4600 cassette (12-28), and Veloce shifters (which include all cables). With shipping, it is $309. Buy a J-Tek shiftmate for $40, and you are all set up for an all new drivetrain for $350-360.
If you want to do it for less, get a 9 speed cassette and hubbub the cable, so you don't need the shiftmate. Then it is $307.
This is for all new parts. You don't have to spend a fortune to update the drivetrain.
Thanks again for all opinions.. There are a lot of different ways to go about this little project. It's interesting to hear all the different options everyone has come up with. The new components will give me a very solid and useful bike. I feel that a worn out drive train is worth replacing. I don't want to dress up the bike to much and feel 105 is the way to go. After I get this finished I'll have to send the 5900 to Trek to get the headset taken care of.
Ribble is great I upgraded to Ultegra with them. $420 or something like that for shifters and f/r derailer, it took about 10 days to get to me. Not bad considering alot of places wanted 400 just for the shifters. If your not in a hurry then Ribble is good.