All the Garmins listed on the following page do what you want:

http://www.garmin.com/garmin/cms/us/...rtableplotters

Here are a few reviews on the 276:

http://www0.epinions.com/pr-Garmin_G...w_GPS_Receiver

And on the 376:

http://www0.epinions.com/Garmin_GPSM...n_GPS_Receiver

And the 478:

http://www0.epinions.com/Garmin_GPSMAP_478_GPS_Receiver

Here's a review of the 276 from another site:

http://www.gpsinformation.org/wilson/g276crev.htm

And one of the 376 as used on a motorcycle:

http://www.angelridevideos.com/reviews/Garmin376C.html

Both of these reviews are form the following very useful site:

http://gpsinformation.net/

If you decide Garmin is for you make sure you read the thread on this
newgroup titled "Am I going to hate Garmin more than Micro$oft?"
started by Roger Long.

Happy reading!