Some chords, the empty space in between isn't a big deal - the strings are either damped by your fingers as you change chords or make something which is recognisably OK in between. A classic example would be all or most fingers off an A chord on the up-stroke, then play A normally on the down-stroke. If it sounds intentional, you'll get away with it! :-) Don't make this a crutch though - ultimately, you do need to be able to change cleanly to do this convincingly.

If you use a strumming rhythm like "down-up-down-up-down-rest" for 3/4, you can change in the rest without anyone hearing. For starting, just do something slow and easy with only 2 or 3 chords, like Clementine or Amazing Grace, just with down-strums, and don't rush it. The classic mistake is to play quickly when you've got the chord there, then a 5-second pause while you change, then another few bars - the best answer when you want to do a song, especially when you're singing, is to play at a speed you can do consistently, including the time taken for changes. Trust us, it will speed up.

Time-wise, I think it took me about 6 months to get 3 basic chords pretty sorted. Not that I stayed playing 3 chords all that time - I'd gone through other new and interesting chords to screw up, like B7, and progressed onto cocking up F and Bm in a random fashion. And to get a strummed tune that was recognisably what I wanted, and at the speed I wanted - hmm, maybe a couple of months. But I was still playing the other stuff, and it wasn't until 6 months or so later that I could consistently finger-pick those same basic chords with any sort of consistency. Finger-picking is the more stringent test - chords will still sound if one or more of your fingers aren't in place, but finger-picking just won't do anything!

One thing to remember. Playing guitar is like playing chess. You need to learn what all the moves and rules are, and for a while when you're learning you forget how to do stuff. It doesn't take long to learn it though, and anyone can learn the basic moves and play a roughly OK game (or song). But to play really well at the world level - that's where natural talent and years of practice comes in! Rick Fielding's got it, Clinton's good too - me, I'll never get paid for doing what I do! :-) Doesn't stop it being damn good fun though...

Graham.