Before you dump the money into a local fitting, give this a go:
Competitive Cyclist Fit Calculator
It's by far the best one I've seen, and if you take your time, follow the directions exactly, it will get you 90% of the way to an ideal fit. You're always going to tweak slightly, whether after a calculator or professional fitting, but this one tends to be very very good ..
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http://anotherdoorat...theinternet.org
Cycle related blog entries, including a few 5 minute reviews:
http://anotherdoorat...tegory/cycling/