Hello Larry,
I purchased a plane through Trade-A-Plane online--similar to E-Bay really...and did just fine. I put some money down with the mutual understanding that if the plane was not as advertised I could back out. I knew I was getting a high-time plane with the understanding I'd do an overhaul, but wanted a good, solid plane in other respects as well, that was IFR.
Not sure all E-Bay deals are like this, but you can find good deals.
My buddy Fred, who I fly with all the time and who is also a member of this club, just purchased his 1975 C-150M on E-Bay in Nov of 2007, and it has been the most trouble-free of all the Cessna's that fly here with us in the KEYSTONE FLIGHT on the East Coast. He just finished his first annual with almost no discrepencies!
I noticed you are from the UK! Assuming you purchase outside the Kingdom, I take it you will have it shipped there?
Best of luck...and if you find any in our areas, perhaps you could ask some of us to check the aircraft out for you for another opinion. If you'd like to travel here to the East Coast, let me know and we can put you up for a time...we hosted a Brit from Cambridge this last summer who was hear coaching soccer for a time - very nice visit.
Warm Regards from Carlisle, PA.
Mike Marra