The majority of the these events are within 1-3hrs of our house. You can sign on, on the morning for most of them. They are all mass start or in waves for the really popular ones.

Here's a few of the sportif calendars:

France:
http://www.velo101.com/cyclosport/calendrier.asp

http://www.cyclosport.com/rubrique.php3?id_rubrique=38

Austria, Switzerland, Italy, Germany
http://www.radmarathon.at/index.php?rmlang=en