Hello warmshowerers!
It was great to find this website. We are Nathan and June, taking a three month tour of Europe starting in Budapest along the Danube trail, to the Via Claudia Augusta, and then hopefully around the coast of Souther France, Spain, Portugal, through Paris, to Amsterdam. We have been very grateful to be part of such a wonderful bike community in Minneapolis, and hope to find the same around Europe. We are looking for suggested route along this path, but are completely open to any suggested routes in Europe. Any tips, pointers, advise would be very helpful. Also, riders welcomed! If you are traveling along this way around this time, feel free to post and come along. We are looking forward to meeting tourers along the way. We will be camping the whole way, so suggested routes with the options of free camping would be great. If you have any questions about trails in and around Minneapolis, feel free to ask also, we will do our best to help.

For east - west:
I would suggest the Eurovelo 6 route. You can find more information including maps at http://www.eurovelo6.org/ or there is an wiki for GPS track info etc. located at http://en.wikipedia.org/wiki/EuroVelo#EuroVelo_6
There is a nice bicycle route with signage etc. that runs from Brussels to Amsterdam called the LF2. There are maps available online at http://www.fietsroute.org/Cycling.php?fietsroutes=LF2
Enjoy your trip!