Im not sure why everyone is being so unhelpful.
Are you looking at advertising on the actual cn website? That would be expensive.
I assume you are asking if there are any cycling sites where you can advertise your house. really you would be looking at registered with the normal b&b sites, or holiday sites and specifically stating that you welcome cyclists. Off the top of my head I dont know of any specific cycling sites that do that. You could also try approaching some of the companies that offer cycling tours.
Do you have a website or anything, worth setting up a simple website with the property, views of the area, maybe some cycling routes already laid out as gpx files so that people can view them. And then take it from there.