Think of somewhere in your town that tourists love to visit (if you live in really tiny town you might have to go on a daytrip to do this excursion). Go there, and take your camera with you. Your mission: to photograph the tourists.
How you do this depends on the kind of person you are. You could take surreptitious candid art shots of tourists taking their own photographs (how post-modern). Or you could politely ask them to pose for your camera in front of the attraction, and ask them who they are, where they’re from and what they came to see, then write a little bio to go with each photo.
If you prefer to be part of the finished product and you live near a really popular attraction, try standing near people as they're lining up a shot, then walk in front of the camera as they press the shutter. Do this twenty or thirty times, and you could end up in photo albums in Madrid, Sydney, Osaka and Toronto.