When travelling almost everyone wants to enjoy a local meal. It's part of the travelling experience. If you're not careful, you may end up in an expensive, "extremely" tourist-oriented place, which may not even represent the local gastronomy.
How do you pick a restaurant? Where do you search for information before travelling? Are there any good online guides?
On the spot what are the dos and don'ts? Do you ask locals? Are they a good source?
Note: The problem with locals is that sometimes they try to be extra nice with you and will send you exactly to places you want to avoid. They don't eat in those places, but it's common that they think it's a nice place for you, since it's always full of tourists :)
One of the problems with most review websites is that restaurants go into a positive spiral. They get attention for some reason. From there, they will attract more visitors due to their position, and of course, those visitors will review them again, reinforcing the spiral. That means one may be losing other, maybe even more interesting possibilities, if only looking at "tops".