Travel Insurance is recommended for ALL travelers. Don't forget to get a policy for your trip in Europe:
If you are an American citizen you will not require a visa in Europe but if you are a foreign citizen you will need to check whether you will need the appropriate visas. CIBT, Global Visa & Passport Professionals, can assist with getting visas for you as well as new USA passports if you never got one!
http://www.cibt.com/home.aspx?Login=44503
As a US citizen traveling abroad you can learn about the destinations on the State Department web site.
Lonely Planet - www.lonelyplanet.com
Fodors - www.fodors.com
Michelin - www.viamichelin.com
Visit London - www.visitlondon.com
Paris - http://www.paris.org/
Brussels - http://www.brussels.org/
Rhine region - http://www.about-germany.org/regions/rhine.php
Munich - http://www.muenchen.de/home/60093/Homepage.html
Salzburg - http://www2.salzburg.info/
Alps - http://www.alpseurope.com/
Venice - http://www.venetia.it/
About Florence - http://www.aboutflorence.com/
Rome - http://www.rome.info/
Greek Island Retreat - http://www.poros.com.gr/?lang=en
Athens - http://www.greece-athens.com/