If you use the facility you can choose anywhere on a map and find all sites within 5, 10 or 20 miles of that location and specify your requirements too.
You will also find loads of visitor reviews of the sites too.
There is also a campsite at the Black Horse pub at Rawcliffe Bridge, near Goole. It's not listed on here. I'm not sure if it's open all year or it's facilities. I've always planned to stay here to walk along the canal & Dutch River but haven't got round to it yet.
Yes the Black Horse campsite is open all year. We walked there from Dobella Lane Farm and asked about the site. Has a few EHU's and toilets and showers.