There are a few ways I know that you can go about this. First, you can use anim8ors built in UV tools,and from different viewports you can select faces, then planar map the textures on. Another way would be to actually use a program such as UV mapper or Lithunwrap to unwrap your 3d model and create a texture using it as a reference. Lastly, there may be a parametric cube plugin that is UV mapped when created, though I haven't been able to find it. You'll find info on anim8or's UV mapping tools in the manual, and you'll find information on UV mapper and Lithunwrap by googling them.
Hope that helps!