I've used tons of the online route mapping sites/apps, and the one I like the best (by quite a long way) is http://www.gpxeditor.co.uk/. Been using it for a few years now and still really happy with it.
I even made a development suggestion to the person who runs it and within the week it was there!
The OP has an etrex which generally work better with gpx route files. I like the look of the gpxeditor website but i see it can only produce gpx track files which may not be best for an etrex user.
I've used tons of the online route mapping sites/apps, and the one I like the best (by quite a long way) is http://www.gpxeditor.co.uk/. Been using it for a few years now and still really happy with it.
I even made a development suggestion to the person who runs it and within the week it was there!