I believe your geocoin was in a cache that was stolen earlier this year. If you note the last post on 1/17/09 (DrStrangeLv) he thought he dropped it in 'Take Me Out to the Ballgame' (GC1A3DC), but he actually left it in 'Chamaeleontide - Ride the Worm' (GC1130H) which was in the same area. Unfortunately that cache went missing this past spring.
Sorry for the bad news, hope that clears up the mystery.