I'm curious ... Do you create a waypoint on your GPS to mark your vehicle's location before you head out in search of the cache?

Its also a good habit to create fast (unnamed) waypoints at convenient places while traveling. That might have easily answered your question about how far you'd walked.

Do you look at any USGS topo maps of the area first? They might have shown you the Jeep trail ahead of time.

I'm a big fan of ExpertGPS - a $60 PC-based waypoint/route manager that not only lets you create/store waypoints and routes on your PC and upload/download them to your GPS, but it also provides on-line USGS topo maps and aerial photos at no extra cost.

They have a free product called EasyGPS that has just the waypoint and route manager w/o the maps & photos, but the topo maps on-line are well worth the one-time $60 fee.

See http://www.topografix.com for more info.

(I have no financial stake in the software/service - just a user)

Ken K.