I've done it 4 times and been to; the New Forest, Kent, Ben Nevis and Alicante in Spain.
What worked well for us was to work things out by phone with the swappers; did they want bedding / fridge stocked / milk / etc.
Also, we asked them what sort of things they were interested in visiting - and put together a pack of information for them to help. We had a folder of local information; shops, parks, doctor, supermarkets, etc. as well.
Make sure your description's well written as this is the piece which attracts potential swappers; house details, local attractions, etc.
Given your location you should have no problem in attracting house swappers. The other side is to work out where you'd like to go, but remember to be flexible.