I decided not to do a very complex scene, so you can notice the importance of a good texture-job. I spent half a day making this simple mesh. It´s only two walls, a column and some details for broken archs.
I just wanted to concentrate on texturing.

Here is the wire mesh.

And here the scene with (only) one direct light (+ the skylight).

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After creating this I inspected all of the three TEXTURE CDs for taking the pics I was gonna need. I chose two differents brick-textures, their respective bump maps, some stone, a ground and some pics with dirt, bare patches and masks. Some pics I chose had not the color that I wanted in my scene. They were changed later.
The images below show an example of the chosen maps.
With the Texture CDs it's hard to choose only a few maps. These CDs are full of high quality images!

When I had chosen the maps, I took renders from the front side, the left side and some renders of custom views without any kind of texture. I apply map coordinates with these clear maps so I can fit the map in the right place.
Then I opened the maps in Photoshop and started tewaking them a bit.

I think that the really important thing in texturing is the way you combine your maps. A good idea for mixing textures is takeing some dirt maps to make selections over another maps. Another great way of getting really nice results for concrete bare patchs is paste pieces of them over the brick map, take the bare set to 0. Choose Hard light for blending mode and hand remove corners to blend the spots in the wall. Remember to have a base noise, for when you clear the bricks under the bare. If you don't, these bricks could be visible under the bare patches (see pic below). As you can see there are infinite possibilities.

After finishing the maps, I started to work on the Bumps. You'll allways want to emphasize some areas (like bricks' gaskets). I assigned the bump maps to the specular-slot, thus I can better control, where I want highlights on concrete parts of the scene.
Here is an example of process.

That's all. I hope you find this little tut usefull.

Finally I would like to congratulate 3D TOTAL on the Texture CDs. I have tons of maps on CDs and HDD, but there are many textures and maps on the CDs that I haven't seen before. All the textures are high quality and two sizes (medium detail and hig detail) are available. The maps have been very usefull to me. The image of this mini-tut has been mapped 100% with the maps included on the Texture Cds. Variety, dirt maps, masks, bumps, material libraries....
It's a great job.