I want one soo bad I can taste the stained wood case that holds it together!! I really need one. Fast. I got music to get started on!!
Your best bet may be to keep an eye on eBay, they come up every once-in-a-while.
You might also keep an eye out for a MultiMoog. It’s a lot more machine for not that much more money on the used market. With it you’ll get a second oscillator, touch sensitivty, some new modulation routings, and another octave of keyboard.
there are usually a few on ebay, but make sure you’re buying from a reputable seller who knows synths
i bought a micro last year from a seller who had all positive feedback and who swore up and down that the board was clean and played in tune.
his $400 “buy it now” seemed like a great price (after all, here in NYC music shops, a nice micro will fetch $500-600) so i pulled the trigger and picked her up.
much to my dismay, upon getting the board, it was so out of tune (with the lowest 4 or 5 keys playing only a few cents apart from each other!) that it needed a whopping $300 worth of repair, tuning and cleaning to be put into top shape.
i could probably have gotten it done a bit cheaper, but the repair was done by one of NYC’s best synth techs and the board plays and sounds fantastic now, but still, it’ll be a while before i can get $700 for this micro!
great looking forum!
keep checking periodically for micromoogs available on e-bay and harmony-central.com. also, guitarcenter.com has a new auction site. but, i agree that if you can find a multimoog in good condition, i would strongly consider it. there were only 1000 of them made, if i’ve been correctly informed.
i had a micro from 1978 - 1983 and i was still getting new noises out of it after five years. the multi is like a micro on steroids. 
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2549320457&category=1289 There’s 6 days left on it.
Hope that helps
Oops… Didn’t see that James posted that .
“I’m embarassed” 
a good place to check out is www.analogsynths.com they get tons of vintage gear in all the time and they are able to service/refurbish them.