Here's another link for sessions around Milton Keynes and surrounding areas: www.session.musician.org.uk
The nearest one of these to Aylesbury is probably the Slapton session on the last Thursday of the month, off the B road between Leighton Buzzard(where I live)and Ivinghoe. There is also the one at Heath & Reach on the 2nd Sunday evening of the month which may not be too far for you.
There is also another small one, not listed, held at the Five Elms, Weedon, - just North of Aylesbury - on the 3rd Monday of the month. Mick Brooks often goes. However last month this was affected by the Performers Rights Society 'police' which I moaned about in another thread at the time.
Look forward to seeing you at some of these sessions - and ducks are welcome as well if they can quack in tune !
Sally M