NaviGadget: SnowRanger from Mountain Dynamics is a set of maps that can be downloaded to Garmin or Magellan branded GPS navigation systems.
They have the resort maps for 64 North American, and 420 European ski resorts which include everything from trails, chairlifts, parks, lodges, parking lots and much more.
North American version runs on both Magellan and Garmin whereas European maps currently only work on Magellan navigation systems. Also you can buy regional maps for most of the regions if you don’t feel like paying too much.
They work on Garmin Nuvi’s too. All you have to do is insert the SnowRanger memory card into your device, and check the box on the next screen to show ski maps. When you are on or near the slopes your nuvi will start showing the correct map.