Meyer did research and found a place like Forks so vampires could be outside. JK just made one up.

It's called the power of imagination people! It takes more effort to fully create a new working WORLD then to find one on a map. --side note: which is why Tolkien and LOTR is awesome!!!---She did a lot of research herself to figure out how everything would work, so that it was logical and could happen...with a little bit of magic :);)