Elizabeth,
The first thing you'll need to do is check EACH of the Chargers, etc. you'll be travelling with, to ensure these are ALL designed for "world operation" from 100-240 VAC.
Monster Cables manufactures a small "travel" power strip that will tolerate operation on 220 VAC power systems. As you noted, you'll also need a Plug Adapter.
You could also consider a product like the ChargePod that has been mentioned in other posts here. I used one on my last trip to Europe, and it was fantastic to be able to charge six electronic gadgets simultaneously.
Also, could you advise which network your Cell phones are with? Unless your service is with AT&T or T-Mobile, your phones likely won't work at all in Europe.
Cheers!