Check out the noticeboard at your local flying club and start asking around in the bar. Usually the best source of information for either shares or whole aircraft. Also search on the private flying forum as there is usually a couple of threads a week at least on this topic. Lots of cans of worms involved so make sure you do your research. Personally I would go for a no capital group. We are about to enter a recession and selling your share later on could end up being a nightmare, or nigh on impossible whilst the ongoing monthly overheads will still need meeting.