Sorry for not coming back sooner with an update. To be honest I was a bit creeped out that more than one of you had looked on Rightmove at every single house for sale in the entire county. I mean, there are literally thousands, who has the time for that?!
But also I didn't want to be like the Victorian safe poster and some of you did offer some helpful suggestions so I am back.
The bad news is, this is looking more like a scam. The council don't have any record of it and the local landowners and parish council know nothing either.
Roger called a street meeting and the 10 houses that pay agreed that a "man from the council" had come round years ago to explain what it was for and they have all paid it since. The other house that doesn't pay and us are much newer to the street which explains why we don't pay and neither of our solicitors mentioned anything when purchasing.
Some of them have a direct debit set up and some of them send a cheque. The bank details and address are different to the council tax ones 
Roger has reported this to the police and I'm awaiting further updates from him.
Some of them want to keep paying it because they are convinced it's real and don't want to get behind on their payments. Two of them think we are just kicking up a fuss to try and get out of paying it 
The general consensus at the end of the meeting was that it might be a scam, but it might not be. I'm convinced that it is
Sad news all round really (but Rodger did come and now my lawn with his new mower!)