Do Your Homework
First read this documentation https://buy.garmin.com/shop/shop.do?pID=30120 https://buy.garmin.com/support/manuals/manuals.htm?partNo=010-00779-00 You will see there that "with Legend's 24 MB of memory and USB port, you can download map with data from Garmin's entire line of MapSource® mapping products.", which means that all of the Garmin range of *.img map files are kosher as far as the Etrex is concerned. Besides, after you download and install MapSource on you PC, you will be able to use it to send tracks, waypoints and routes to your device - using gps file types
