Get the road race permit form from your local region, try looking on http://www.noeaa-athletics.org.uk
This should give you guidance on what you have to do (police, first aid, risk assessment, course measurement, permitted distances for age groups etc).
If you apply as running club the permit should be free, otherwise it will be £20 or £30. The permit will give you some insurance cover, this is what the £1 unattached levy is meant to cover.
The police can be quite variable, my local police all seem to be runners and all they want to know is whether any police assistance s required. If you are running off-road then you shouldn't have any problems.
Good luck.