If I read your question correctly, you want to use the diffuse map and the displacement map and make them line up with each other, so that they are aligned.
To do this, all you have to do is use the same UV map for both images.
In short, create two image nodes, and load the diffuse into one, and the displacement into the other. Plug the diffuse into the color slot of an emission node, and plug the displacement into the height slot of a bump node.
Add a geometry node and plug one of the mapping types (UV, generated, etc.) into the vector slot of both of the image nodes (use the same mapping type for both images).
Plug the emission shader into the shader slot of the output node, and plug the bump node into the displacement slot of the output node.
For Blender Internal, the process is a little different.
You'll only need one material.
But you'll need to add two textures to that material. One texture should be set up like you expect for a regular image texture.
The other should be set up like this. Basically, you'll have two textures, one with each image. For the diffuse image you'll check "Diffuse: Color" and for the bump map you'll check "Geometry: Normal." There may be other bump map settings below that, but this should get you close enough to see some results.
Keep in mind that Normal Maps are different from Bump Maps. Normal maps are usually bluish, and bump maps are always gray-scale.
There's also a displacement modifier, which you can use your grayscale image with. You'll still create a bump texture, just like normal. Then choose that texture in the box on the displacement modifier. To make it line up with the diffuse/albedo map, just change the "Texture Coordinates" from "map" to "UV."
Then you'll see a new box called "UV Map" where you can specify which UV map to use. Just choose the same UV map that you used for the diffuse map. You can give UV maps custom names, too, which might help you choose the right one. There are lots of places to specify UV maps, as long as all your images are using the same UV map, they'll line up with each other.
There's more information here for both Cycles and BI.
That should do what you want.
