In reply to Ste Brom:
Sounds like a lot. Hard to compare though.... I use FASIC in Edinburgh (the University sports science/physio place). They have podiatrists that I have been happy with. Consultation is about £40 I think, and they check all sorts of stuff and recommend exercise etc as required... Orthotics themselves are about £120, carbon fibre, custom made etc. When prescription needs changed or they get too worn its about £40 to 60 (memory) to get them refurbished to new spec.
Worth their weight - I wear them constantly, find them comfy, find my knee issues are resolved and they allow me to buy pretty much any 'neutral' running shoes without worry as I know the orthotic will correct the shoe, rather than trying to find the shoe that precisely fits me.