Strictly speaking no - but if you include on your website a template of your own logo and webaddress that your users could download and printout on to sticky labels 'for their own use' then if the council come and complain to the site you can point to that page and shrug your shoulders.
Make sure that you can produce download or page view stats if they come a knocking though and you should be fine
Another one I saw recently was to write the web address in chalk on the pavement so that when people are walking along, they notice it and it sticks in their head. The chalk gets scuffed away over time and disappears pretty quickly when it rains so there is no evidence left
