Join Date: Oct 2009
Location: Northeastern Ohio
Vegas has a point. You can get tons of info online these days.
I've been using Google maps and Bing maps together to help determine a route for a future tour. Using the aerial photo ('satellite') you can often get a good idea of the road surface, whether it's gravel or paved, and how well. You can zoom out and get a rough idea of the traffic on a road (try using the shadows to determine rough time of day). And using Google street view you can even check on how much of a shoulder is available.
You can use hillmaps as well if you like to see the topo for an area to judge the climbs.
Granted none of this is foolproof, but I've had pretty good luck so far. Just be prepared to be proven wrong on occasion.