From having lived in Germany for 11 years I can tell you that everything you bring better be "universal voltage" (110v-240v) and buy your own German-style plug adapters for EVERYTHING.
The adaper plug you'll need the most (Germany and Eastern Europe) is for the following:

I know that the Czech Republic uses this one as well as Sweden.
I know, I've been to every single country on the continent at one time or another.
SOmetimes you run across a weird plug that looks like it but also has a grounding prong sticking out of the socket but most grounded German-style adapter plugs have a hole for it so it's no problem.
For trips to England or the Middle East get this one:


More info here:
http://users.pandora.be/worldstandards/electricity.htm

All of my Nokia products have been purchased in Germany and they've worked just fine in Europe, the United States, Africa, Middle East, and Australia.
For your N800/770 and any "new" Nokia phones you can buy new power supplies that fit the plugs there at just about any phone shop or big department store. Swing over to Munich, Germany if you can and check out the Media Markt there. They usually have a ton of cell phone accessories.
And remember, over there a cell phone is called a "handy" and not a "cell phone".
Well, at least in Germany. England calls it a "mobile" and so do a lot of other countries. But Nokia products dominate the continent there so you shouldn't have any problems at all finding accessories for it or technical repair support.

As for radio, don't worry about it too much. Thing is, the American style digital FM radios skip a freq and only land on the odd numbered digits whereas in Europe they do no such thing. Luckily the Alpine radio I had in my SRT-4 in Germany didn't have such a limitation. Bring along an FM transmitter for your iPod and you'll be fine. Also, make sure you get your international driver's license or you can forget about driving in Europe.
For TV broadcasts they use the PAL standard (625 LPF) versus the ol' NTSC standard (525 LPF). If your video equipment is NTSC-only then just go ahead and leave it at home. Also, Europe is light-years ahead of the U.S. when it comes to digital broadcasts and you can pick up a USB DVB adpater for your laptops pretty damn cheap there (well, I know you can in Germany at least).
And it's cell phone heaven over there. You'll see phones you didn't even know existed or were possible.
I just came back from two weeks in the states and it was pure hell for me in the US. Every cell phone sotre I walked into I laughed my head off at their weak-sauce "selection" of cell phones. My N80ie (which I've had since its European debut..EU 400...ouch) continues to blast them all away when it comes to features.
They've had 3G video calling in Europe for quite a while now.

For wall-powered USB hubs, I recommend buying one in Europe versus bringing one from the states. The reason being is that most wall-powered USB hubs in the states are 110v only whereas the ones in Europe are usually 220v if not universal 110v-240v. I still have a few I bought in Germany that I use all over the world with plug adapters since they're universal voltage.

As for your iBook, Apple does have stores on the continent but don't expect to see too many Apple products in regular stores. Check the Appel website to find the closest store or authorized retailer near where you'll be living.
You'll get quickly addicted to the digital lifestyle present in Sweden...I did.
The Czech Republic I mostly went to in order to go drinking in Prague with friends. It's only a 5-6 hour drive from Frankfurt via autobahns. The CR does have a toll-road system for their version of intertates/autobahns so make sure you buy a sticker for your car or you WILL get a ticket and pay a fine. You'll probably already have one on any car you rent in-country.
I know from past experience but I was able to bribe the cop pretty easily and get the hell out of there and up into the Silesia region of Poland.