There's nothing like being there yourself for a writer to get the flavor of a story's setting. I just returned from a vacation in San Diego County, where my current work in progress is set, and it opened my eyes to new facts and useful details. I've swapped one city for another that fits better for where the MC lives. Look out, keyboard, my fingers want to fly!
I still might need something later on that I didn't capture by camera, notebook, or memory, and it's unlikely I'll get back there again soon. Even if you've never traveled to the location you're writing about, there are several research tools to help. Find an Internet or magazine photo that is a good representation of what you want to describe and tape it near your monitor. Check out Google Earth for both overhead shots and street views of real locations. Talk with someone who lives there. Then again, you might find places in your writing where the imagination is adequate enough to get it right.
I read Rachelle Christensen's Wrong Number last year after having been to the ice caves that she describes in that book. When my perception of the place matched her descriptions, my mind's eye candy became even more delicious, more stimulating. That's what we're striving for.
How do you make a setting or description come alive?