This day in age the vast majority of the US public has internet access. For whatever reason there seem to be plenty of restaurants that still don't understand that they need to have a website, and it needs to have certain basic information such as: phone number, hours of operation, and perhaps most important of all a current menu with prices.
I always Google a place before visiting for the first time, or if I'm not sure where to go I just do a search for the type of cuisine I'm looking for and wait to see what pops up in my area. I am many more times likely to go somewhere that I know will be open and where I can see the menu and decide what I might like beforehand as opposed to just driving out and testing my luck, and I don't think I'm alone here.
It's 2012, websites are available for next to nothing, there is no excuse not to have one. Even one of those insipid Facebook fan pages is better than nothing, as long as the menu and the basic information is posted. A gourmet hot dog joint in my town has the Facebook fan site, but no hours listed, and no menu, just a bunch of photos of people attending some event there, which tells a potential diner exactly nothing.
No matter if you have three Michelin stars, or run a mom and pop take out joint, there is no excuse not to have your phone number, hours, and current menu with prices available on the web.