The site was Northborough, grid ref TF 1557 0854. The site is described (pre-excavation, of course) in A Oswald et al (2001) The Creation of Monuments: Neolithic Causewayed Enclosures in the British Isles, published by English Heritage. A transcription of the cropmarks is featured on page 92. The site was discovered in 1996. The Time Team website (www.channel4.com/history/timeteam) has some info on the excavation.