When people talk about using maps for stuff, I often wonder where they get them? Unless a prop/figure comes with its own maps, how can you make them? Like a reflection map or a transparency map or something? Do they just use a texture map that’s been reduced to greyscale? (because maps have to look like the object your using them on, right? I mean like the bump map for a face, looks like a black and white version of the texture map)
There’s an excellent post here from Totte about how to apply a bump map to something that doesn’t have one (you don’t even have to change it to grayscale, though “real” bump maps are—keep in mind that light colors equate to the raised bumps and dark colors become dips in the surface, so if the diffuse texture has color variation that doesn’t coincide with where the bumps should be, for best results you may need to make some changes in an image editor).
Here’s another good tutorial on the subject.
More generally, people do anything from mix and matching maps (take one character’s skin, another’s eye textures, and a third character’s teeth, for example) to making their own from templates and/or merchant resources. All depends on the situation and on your skills and patience.
I like your new avatar, by the way.