Dave at Bicycle centre is a hard man, yes. Roadie who just opened cyclescape is a regular rider, but a bit busy with the new shop at the moment to ride much. Phil Orr at gove is a hardcore xc/road rider and top mechanic and Tim at Navajo has as good a workshop as any.
Personally, I say that any one of them will look after you well. It might come down to location, or just who you get along with/ride with. If i recommend one over the other, it would be more biased towards friends than anything else. I have never had a bike service in 15 years, just learnt to do it myself or got a hand with the occasional fork from stoo (who you'll catch at the hard men most weeks)
Playing with bike maintenance is fun, particularly if you're practically inclined, like, oh, an apprentice welder/metal fab man. Buy some basic tools, you can get kits cheap, and have a crack. You might even be able to claim them on tax ;-)
Google bike James for technical info, and YouTube vids for most stuff. You really can't fuck up the basics like drivetrain, brake adjustments, cranks/bottom brackets and headset tightening, so just have a play if you have 30 min spare.