You could always buy a share in an aircraft, these range from £1.5K to £7K depending on it being a third share or a tenth share and aircraft fit/type etc.
I paid £4000 for a tenth share in a PA28, it works out about £40 per hour wet, £4K was a bit on the top side but it's got an IFR fit, GPS, auto-pilot etc. If you went for a C150/152 that would be cheaper.....and slower, but hey....more hours !
Once you get the aircraft sorted do plenty of flying via Jersey, Guernsey.....the fuel is half price and VAT free.....landing fees are faily cheap.
It sounds a lot of money to tie up, but it makes sense if you want to build > 200 hours......the aircraft should not devaluate at all....just be carefull and make sure you join a well run group.
The US is good for hour building but you have to add on accomodation and your air fares....there are also some quite badly maintained aircraft around in the US....I've experienced a couple of nasty incidents....
Fly Safe
Mer....