#1: Black leather boots can sometimes look more "cheap" or synthetic than the same boot in brown leather. The black color forgives a multitude of sins (which is why a black dress in a cheaper fabric can still look great) but often doesn't get the great patina that brown leather gets.
#2: You can wear brown and black together. Case in point:
Target Earrings and turtleneck
I would do the same with a black dress, black tights and brown boots or a black tunic over leggings with brown boots.
I could easily pair the same outfit with a dress or jeans.
#3: Brown leather boots are simply awesome. Not a real reason, but I had to throw it out there.
In general a pair of leather boots will start at about $100, depending on the sales. Some of my favorite more affordable options are here, here and here.
What about you? What do you think of combining brown and black?