I got a Magellan Maestro 4010 from Sainsburys for £29.99 (Actually I bought two, one for a christmas present for someone else) They aren't as good as a Tom Tom in mapping terms but for thirty quid I'm not whinging. Especially has it has bluetooth too !
Updateable and Safety cameras preloaded.
(I just had to drive to Harrogate to get them !!!!)