Just back from enjoying excellent views of around 8 SE Owls on rough pasture fields at Blueberry farm, near Maidwell.
It appears the best way to see these birds is take j2 off A14 (if coming from the midlands), head south towards Northampton on A508 for just a few miles. Go past Maidwell itself on the A508, and at the small hamlet of "Hanging Haughton" take a right at Manor Road (you can barely see the village from the road and there is just a single small sign for "Hanging Haughton"). Manor Road leads thru the small village. Stay on Manor Rd, do not be tempted to take tracks off it. At the end of the small village it bends left and then becomes a rougher tarmac rd which actually says 'unsuitable for motor vehicles'. Its fine though, with care. Carry on for about one mile, past a signposted footpath crossroads junction (some cars park at this point), and drive on past a barn to your right and on across a field. At this point you may wonder if you can drive on, but you can on what is a hardcore track. About a quarter of a mile past the barn, you come to a rough pasture field and around 8 birds were hunting over this field when I got there at 2.30pm, affording great views. You can park easily by the field itself, which several birders and photographers were doing.
The owls currently hunt over the field from mid afternoon, and move northwards up towards the Blueberry farm complex a good half mile away. So I would say get there by 2.30pm, to enjoy the owls here.