I'll be in Europe (all over, from london to Athens and lots of places in between) for over two months this starting in May.
To ease the pain of communication I was wondering if there is a mobile phone/company that covers the entire continent (or most of it) or whether I should get a preaid calling card type thing.
There are mobile phones (like TMobile's) that allow you to use your mobile phone wherever in Europe or in the USA you are. Only when going to Asia I switch to a different phone model - I could use it on all three continents, bvut it is too heavy, so why bother with it if you only go to Europe.
A possible disadvantage is the cost - since the company pays my phone expenses (no matter whether private or business calls - a little perk) I don;t really know how much it cost to use your US mobile number on other continents. Another disadvantage - since people calling me often have no idea where I actually am (they think I am in US Eastern time) they often wake me up in Europe in the middle of the night if I don;t turn the bllody thing off.
If you have a tri band phone, you can use it in Europe with your American provider. This is going to be quite expensive though but it is the easiest option, especially for incoming calls ... if you don't have a tri band phone it's useless outside the americas as the rest of the world uses a different system.
All countries in Europe have different providers (although technically a lot are owned by the same company) and phone numbers so you can't avoid having different phone numbers in the different countries and switching providers if you want to make it as cheap as possible by using prepaid cards. Have you considered one of these renting firms? I am sure their prices come at a premium but for travelling in Europe it still might not be a bad idea. I stumbled across this one the other day for example: www.smartcoms.com
If it is for calling home, I would just buy the 'old fashioned' calling cards that give you really good rates from pay phones!