For guitar #1 with the broken wire - no shortcut I can think of - if the wire is still long enough you'll need to solder it back on, or maybe replace the wire as well. Soldering irons are pretty cheap, and you'll probably need one again if you're going to do your own repairs.

On the squire with the trem fallen out - it might be easier than you think. Is it still strung at all? Basically, all you've got there is a couple of screws in the front of the body that the bridge slots under, then you just have to hook the springs in at the back - it's more obvious looking at it. slacken all the strings off - hook the bridge edge under the 2 screws in the front, and then see if you can hook up the springs around the back...

I guess the 12 string with the busted strings will be the easiest to talk about, but none of these sound like too much of a nightmare.

Maybe see if you can get hold of a Dan Erlwine book as well - that guy covers pretty much everything... :cool: