I see Adorama have a few listed in their used section:
contax g2 : Buy or Learn at Adorama
Also 7 on Amazon of all places
Amazon.com: Used and New: G2 Camera Body
Although on closer inspection they are not all G2s!
Camerapedia give it a glowing review
With its titanium clad body, sophisticated electronic rangefinder and superb lenses, the G system has not been equalled in the years since its introduction. To its fans, the Contax G2 is the finest 35mm camera ever produced. The Contax G system is still available in quantities in the used camera market at prices much below the Leica M system. Users who do not need lenses faster than f/2.0 will find that the Contax G system is still unmatched in camera performance with lens quality equaling the Leica M performance in most cases.
And you may already have found this, but this is a price guide to buying G series
Contax G Lens Page
Contax G1 Body $ 200-375
Early G1's cant use the 21 or 35 lens w/o upgrade
Contax G1 Body (modified, "green label") $ 225-450
Factory modified to use 21mm & 35mm lenses
Contax G2 Body $ 375-500
Black version sells for about $ 200 more
Contax G2 Body Black $ 900
16mm F8 Hologon $ 1800-2100
includes finder & filter
5 Elements in 3 groups
21mm F2.8 Biogon $ 600-800
includes finder
9 Elements in 7 groups
28mm F2.8 Biogon $ 275-325
add $50 if black
7 Elements in 5 groups
35mm F2 Planar $ 350-450
7 Elements in 5 groups
45mm F2 Planar $ 225-300
add $40 if black
6 Elements in 4 groups
90mm f2.8 Sonnar $ 150-300
add $40 if black
5 Elements in 4 groups
35mm-70mm F3.5/5.6 Vario-Sonnar $ 425-550
13 Elements in 8 groups - only fits the G2
Great looking system - if you're passionate about the look/feel/potential I'd say that overrides all purchasing logic.
After all, it's about the emotion when taking the images - and if you're fired up about a new camera/system, you'll enjoy it even more.
That's just me trying to spend your money for you!