Hi Ray Q. Yes the MGS (Maryland Geocaching Society) www.mdgps.org is a great group. I live in Maryland near Brunswick MD. I am always looking for Geo-Buddies to go caching with. According to Google Earth, Waynesboro PA is not to far away.
I have a Garmin 450t GPS that I use for caching and hiking. It's a great GPS as far as I am concerned. I would suggest whichever one you get make sure it is a paperless unit.
Whatever you decide on, make sure to Have Fun.