I'm currently working on a story about a town I'm very familiar with, and I was wondering what the law states on using restaurant names or the names of other local businesses. And just for the discussion's sake, what about the use of global businesses and their products? (i.e. Coca-Cola, Pepsi, etc.)
There are many threads on this subject. Popular products like coca-cola, Pepsi, dr.pepper etc are not likely to get you in trouble for mentioning them unless you make them seem bad (like saying coca-cola makes your character throw up). Using restaurant names is probably following the same "rules", but to be sure you would have to consult a literary attorney.
No problem if you are using the names to make your descriptions of places authentic, just like using street names.
Like Xatron says, I don't think it's a problem, unless said restaurant/product is given a bad image. So, if, to choose a random name, your characters went to eat at Mario's Pizzeria and they had a great time and the food was lovely I think, if anything, Mario would be happy that you've given his restaurant free publicity. However, if they went to Mario's and got food poisoning, it's a different issue and you may not be allowed/would have to consult an attorney.
The restaurants that I use are re-imagined versions of their real-life counterparts. One of the restaurants is shown in a positive light, while the other is shown in neither a positive or negative light. The second just serves as a location, nothing more, nothing less.
names of real products and places and businesses are used in fiction all the time... as noted above, you just have to be sure you're not saying anything about them that can get you sued... all who want to be writers should be familiar with copyright and trademark laws... study up on them here: www.uspto.gov www.copyright.gov and when in doubt, consult a literary attorney...