boundary wall collapsing into my garden and blocking access

[charlotte38]

A few years ago a new owner whose land borders on the left side of my lower garden built a concrete panelled structure but failed to leave any water drainage holes in it.
The structure, which is about eight feet tall,has gradually leaned further and further over into my garden becoming dangerously close to my shed ( now about a 12 inches off the roof) and has now impeded my access to my land behind my shed.
In October 2007 I hand delivered a note to these people asking that they act before the structure totally collapsed which it is bound to do if nothing is done, but they failed to contact me or address the situation.
Do I now send a special delivery note to prove I have asked reasonably for them to correct the situation and where do I stand if the inevitable happens?
My Shed is not new but serves its purpose in housing all my garden equipment.

[Eve]

Try your local council as they should have a facility for reporting dangeous buildings.

May be within the Building Control dept.

[lampgb]

Visit your solicitor. If the structure is a fence? then it should be no more than a certain height. It should not lean over your property. If it collapses then you are due for compensation. If it collapses on you are anyone else then God help them