Close-ups of textures can make interesting images on their own but they are most useful for blending with other images to add interest to plain backgrounds or to give a particular shot a different look / feel. Towns and cities are great places for hunting down textures and once you start looking at detail rather than buildings as a whole, you'll soon find a variety of textures to fill your memory card with. Walls, steps, doors, sheds, modern metal structures, roof tiles and windows are just some of the locations you'll find interesting textures at.
When it comes to kit choices for this subject, zoom lenses are useful for selective cropping while a macro lens will get you close to the patterns you're capturing. Pick up a telephoto lens when you want a tighter perspective. A tripod is handy for when you're using a telephoto lens and will also help ensure your shot's straight. A remote release or the camera's self-timer are tools you'll be using quite often, too.