You might find this useful
If looking for a tomotm, this site can be interesting...
http://www.find-tomtom-deals.co.uk/
BUT
If you fancy a CHEAP satnav solution...
(This info is taken from another forum and is UNCHECKED by me in any way)
Halfords are clearing out any obsolete sat navs that they still have in stock - it will vary from store to store but if you are lucky you might find a bargain! Here are a few to look out for:
AA Navigator - £34.99
Navman ICN 330/530/550/720 - £34.99 each
Garmin NUVI 310 - with bluetooth! £34.99
Garmin NUVI 300 - £49.99
TomTom GO 500/700 - £34.99
Navman N40i - £99.99
Garmin C510 Deluxe - £49.99
There are quite a few more, many stores won't have these in stock but it is worth asking or poping in as you never know!