Van Buren is the red-light district of Phoenix, Arizona.
When people talk about "Van Buren" in this sense, they are usually referring to the stretch of Van Buren St. east of Central Ave. before the road becomes Mill Ave. at Papago Park.
The nature of the area is made more obvious by the overabundance of cheap motels. Most residents of the Valley of the Sun as well as many other Arizona residents know of the reputation of the street.
It's also commonly used in jokes.
Wanda: I have to leave for work now.
Jake: Down on Van Buren, right?
Wanda: No, that's my night job.
Jessica: You're pretty ugly
Jose: That's not your mom was saying last night at Van Buren.
Maria: My new house is on Van Buren.
Justine: Oh, neat, now you can visit your mom while she's at work!
When someone has short hair that has grown a bit too long and it sticks out on the sides like the eighth president of the United States, Martin Van Buren, who was bald with two sticky-outy regions of hair on either side of his head. This happens with normal people who have full heads of hair when their ears make it stick out over the sides.
Your Van Buren is unsightly and it's driving me mad. Just get a haircut already!