Just a few thoughts to add to the already excellent collection that precedes this entry:
The Chapter 7 website really can be useful (as has been said previously)
http://www.tlio.org.uk/chapter7 and their homepage
http://www.tlio.org.uk/about gives other useful links. I highly recommend buying the DIY planning booklet from them, as you'd be lending support to a very sound organisation with a fascinating history. They're 'not for profit', it costs around £15, and the information it contains was hard won over many years by Simon Fairlie, co-founder of The Tinkers Bubble in Somerset
http://www.audacity.org/APO-Sp17a.htm and
http://en.wikipedia.org/wiki/Tinker's_Bubble
It's easy to understand why people can get frustrated and annoyed with planners and council officials, and end up using phrases like 'jobsworths', advising people to tell them to 'sod off' etc etc, however it may be worth noting some of Chapter 7's advice - when you deal with the planners, you deal with a very old, patriarchal class-related system that does not appreciate being told what to do, or that its ideas and decisions are wrong or unfair (even if you believe fervently that they are!). If your attitude towards suggest disrespect, you're less likely to get a favourable outcome.
It may be a bitter pill to swallow, but you have to employ deviousness, charm, smarmyness and whatever other psychological tactic/s you may be able to utilise i