well, we could type one line each, in turn.
Prism, all a click track really is is a metronome recorded at the right speed for the song. Some DAW software, like Pro Tools, has a "build in" click, just set the timing and go. For anything else, you can just use a track from a drum machine.
For those of you who have a 'puter but are going to say; "I aint gotno drummechine", do what I do, because I use free software for most of my initial guide (click) tracks.
Download Bram Bos' HammerHead freeware. It works, its fun, and you can download hundreds of user made sound libraries for it
http://www.threechords.com/hammerhead/
Another thing:
If you want to track to be as tight as a duck's ass (and that is water tight), use a short, tight percussion sound or the "original" click. If you want to encourage a drummer to play with a little bit of shuffle (in other words, with a "live-feel" mild time variance), use a lower sound with a bit of reverb on it.