Check out Big Paws Only a web community devoted to large breed dogs, their issues, and helping them out when the need arises.
I got a GPS unit for my birthday (Garmin eTrex Legend) and have finally gotten into geocaching. I have found caches when I was out with other geocachers before, but this is the first time for me by myself or with my partners (human and canine). For more info, check out geocaching.com.