I have the Garmin etrex Legend. I like it alot. I'm thinking of upgrading to color unit with a little more memory. I like the MapSource topo CD's too. Thepreloaded factory map isn't very detailed. I like having the topo features, extra country roads instead of the majorones, rivers, lakes, etc. It come in handy fishing too.
http://www.thegpsstore.com/ has pretty good prices.