I'm currently sat in front of a PC planning my route from Montpellier to Zeebrugge. (via Mt Ventoux) I plan routes on strava, with the help of streetview, and download to a Garmin edge touring device (pre-loaded maps of Europe plus long battery life). In addition I take 1: 200,000 Michelin maps. I couldn't do without either. This is not the cheapest solution but it works for me.
The Garmin is good for towns. The maps are good back up and useful if you want to deviate from plan.
The best part of the trip is the planning.