at least for me, is the Public Monuments and Sculpture Association's National Recording Project. You probably knew about it; it's been there for years, by the looks of things. It's a geographically arranged list of most of the public sculpture in "65% of the UK". It's wonderful. Best of all, many of the entries have photographs, so if you want to know what a real tourist trap looks like (description) or how all seaside railings should be (description), you can.