Dr Marshall – The easiest source for information on Hexham and Hexhamshire common land is the Northumberland County History. Volume III, Hexhamshire Part 1, deals with Hexham town, and Volume IV, Hexhamshire Part 2, with Hexhamshire and Allendale.
There were two major enclosure awards – for Hexham East and West Commons, in 1755 and for Hexhamshire and Allendale Common in 1792. You can find the awards, and many related papers, at Northumberland Archives –
QRD/2/1,p130 Award on the Division of Hexham East Common and Hexham West Common, 1755; Plans in ZGI plans XXXII/1
NRO 06785 HEXHAMSHIRE & ALLENDALE COMMON AWARD 1792