there is a lot in Sussex.
I lived in Brighton where there is the remains of a stone circle near the pier (now clustered under the dolphin statue on the levels.)
There is a pub on the beach which has a large stone on the cellar floor which once stood on the beach.
Hollingbury hill fort is worth a visit as is Cissbury.
There are longbarrows above the longman of Wilmington and another a few miles back.
2 more at Devils dyke.
There are stones in Hove park and in Patcham fields.
Pick up a few guide books when you get there.
http://www2.prestel.co.uk/aspen/sussex/
PeteG