I have been working with some of the data from The Office of National Statistics and Ordnance Survey.
If you want some lookup tables to find out how wards, districts/divisions, counties and so on all relate take a look here
I would like to write a bit more about this - but honestly UK geography is so confusing and I can make sense of the data but am not ready to make a decent explanation yet.
Some great resources
- UK Election maps
- National Statistics Geodata
- Ordnance Survey Open Data
- Beginners Guide to UK Geography
- Paf (postcode) Programmers Guide