Hi there
You'll not have any issues - almost all electronic's nowadays come with a transformer/power supply with a range covering 110-240v. More than likely though, you'll need an adaptor that will accept the US plug on the 'gadget' side and plugs into a UK socket on the 'power' side. These are very cheaply and widely available here.
Have a look at the US sites such as ebuyer.com, amazon, ecost.com, overstock.com etc to bag the best price for your chosen camera over there. Some electronics nowadays aren't much cheaper in the US as compared to here - but if you shop around you can 'maximise' the savings, plus with the US exchange rate anything bought there will have just that little more 'value' to it.
Get as big as a memory card as you can - 2GB cards are very very cheap nowadays and work in alot of electronic gadgets besides digi cameras. Any larger capacity ones, although cheap - use a newer technology which isn't as widespread in use at the moment althugh it's getting better.
Have a quick search for the camera forums where you'll get good reviews and advice - take that knowledge to the shops and get yourself a good performing model - even if it costs a little more!
Hope this helps!
cheers! DtM! West London & Slough UK!