Time Team did a limited dig of Lincoln’s Inn and the Fields for a show transmitted in March 2009. I stumbled across a copy of the show on YouTube (link to the start of the segment on the Fields 18 minutes in – embedded video below starts at beginning of show)
Also of interest is the post dig evaluation and write-up by Wessex Archaeology which contains a wealth of tiny details about the archaeology of the Fields. What is interesting overall is that, despite the Fields being a large open site that hasn’t been heavily developed for 400 years, they didn’t turn up much archaeology.
Friends of Lincoln's Inn Fields 