The instruction for a JAA PPL must be completed at an FTO or an accepted Registered Facility (or, after April 2012, at an Approved Training Organisation). Consequently, you will have to find an amenable training organisation to take your aircraft onto its books and use its instructors and operating procedures. This is not impossible to arrange but it's not quite as simple as buying an aircraft and finding an amenable instructor.
The current rules for training in permit aircraft are contained in
ORS4-803
Flight training (for any licence or rating) has been allowed at unlicensed airfields since April 2010. The relevant guidance document is
CAP 793