Anyone have a good recommendation for a web site that would allow me to search for US Airways flights to Europe covering several destinations and a flexible time frame?

I'm looking for a way to use those CP upgrade certs before they expire at the end of February (so the flights have to be on US Airways and not partner airlines).

I'm pretty open to most any US Airways destination in Europe (AMS, BRU, MAD, LHR, ROM, DUB, ZRH) but not really interested in trips to TLV, CDG, FCO & GIG. MUC is also a bit iffy since I was just in Germany last December. I don't mind going back but someone else might raise an eyebrow

Ideally I'd like to travel in May and avoid the July/August travel crowds. Plus my GF has at least a week off in May so it would be easier on getting our schedules synchronized since mine is pretty flexible. Depending on where I go I might want to arrive at one destination and leave via another (e.g., arrive AMS leave BRU).

It gets pretty tiresome entering in each city one at a time on the US Airways web site. I tried looking at Kayak and it may be a touch better but still requires entering each city in one at a time.

Right now there doesn't seem to be any bargains out there unless I'm looking at the wrong dates/cities.

Thanks.
Rich