Yeah there are converters for them, but they may not run quite right because of the frequency. Europe uses 50Hz, while we use 60. That affects the motor's speed, and most converters are simply step up transformers, they don't change the frequency.
You can try them though.
Voltage-Converter-Transformers.com sells a bunch of them. They used to have one that's rated for 100 watts (more than enough) for something like 20 bucks. Be sure to pay attention to what kind of plug is on your powerhead. Hopefully, it's a British BS1363, a German "Shucko", or the standard european two round prong plug. You can usually get transformers that already have these connectors. If it's something bizzare like an Iraqi or Australian, or French plug, you'll need to find a "travel adapter" that converts one to the other.
For a guide to what kind of plug your powerhead has, try this:
http://kropla.com/electric.htm#plugs
Good luck!