Morris,
Have a look at the Garmin 60CSx and Garmin 276. A lot of us have the 60CSx, and it works well with topo maps, street maps, driving directions, mac/windows compatibility, good GPS (SIRF III chipset), color screen, small enough for backpacking, and rugged.
The 276C is nice, but it doesn't have the good GPS (Sirf II instead of Sirf III chipset)
Craig