Live music tips?

I've used CoolEdit and Adobe for years to edit songs I was working on, and both programs were fine with it just being me in the home studio, but I always wondered what upper drawer features I was missing out on.  Over the years, I've met some guys who like to come over and jam, and now we're recording together.  Because it's my computer and my programs, everyone is looking to me to get good recordings. 

Does anyone have any recommendations they'd like to pass on for recording live music (not all at once -- overdubs)?  We lay down a click track on a multitrack, then drums, guitars, bass, etc.  I import the sound, track by track, through an Edirol UA-25 into Au, and sometimes record directly into Au (solos).  I would love to figure out if there's an easy way to sync the tracks, and to find out if there's a way to snap live sound to beats and have changes to tempo alter the whole song accordingly.  We use at least a few time changes per song, so snapping would be great, but I can't quite figure it out (I see it's covered pretty well in discussions of looping and MIDI, but we're using neither). 

Any live music guys and girls here that can offer up some advice or tips?

Thanks all,

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