I'm a newbie too. However after searching on-line and doing quite bit of "value" hunting, I found a deal that's hard to beat. If you haven't already purchased a GPS unit, Costco has a great bundle pack. I purchased the Magellan Sportrak Pro for $289 but there is $100 rebate. Included in the bundle for $189 is a car mount, Mapsend software, belt holder, car power adapter and the pc cable.
I couldn't decided if I wanted to spend $125 more for the Garmin Vista which includes an altimeter and barameter. I was relieved to learn that the mapping software included in the Sportrak bundle has elevation markers too!