The Jessops store in Newcastle stocks a decent range of film (but they did sell me some out of date IR film recently- I got my money back). Also try the Jacobs store directly opposite, similar prices but less queing. Another good reason for going to Jacobs is that they sell darkroom chemicals and paper. The Jessops store has no darkroom stuff on display anymore (that I can see).
MPS in Carliol square (as Carol suggests) is a very good professional store but I find them a little bit pricey for film.
Les (from Newcastle)