Thanks a lot! 
 
Your models are very well done and detailed! 
Could i ask some help on some of the materials? I have some issues understanding the specualrity map, for example. I never understand were to use darker or brighter tones. And how the hell i make those aztec patterns become proper spec maps?
Also, can i use such maps on Cycles? 
And just one more question 
 
 
Do you use Boolean for the windows? I do that and my mesh tends to become a mess. 
 
By the way, i use Gimp 
 
		 
I'll Pitch into the specularity bit, 
In truth specularity is really a bunch of "things" to do with how a surface accepts light. 
This is a really important concept to grasp, because most of your texture detail is in the spec. Now, I'm going to break this even further a good spec map, fills three functions.
- Colour
- Reflectivity
- Glossiness
In more complicated shots, I would separate 
all three into individual textures.
 The first would be as madman describes it, it basically lighter in colour then the diffuse. 
  The second would be a "shades of grey" type map where: 
1 = White = Max Reflective Strength
0 = Black = No Reflectivity at all. (like the vacuum of space, )
  The third map is basically a high contrast version of the second, this will determine the clarity of the reflection again same concept as the second map. 
1 = White = Max Reflective Clarity (Think clean mirror)
0 = Black = An Incredibly Fuzzy Reflective Surface ( A rock.)
 And that is the basic concept. 
Normal Maps, and Displacement Maps (One is a bump map on steroids, the latter makes both look like Napoleon Dynamite standing next to Mike Tyson) are also a huge part in spec maps and will help determine how light will fall on a surface.
Also look at these links:
Fresnel Effect
http://en.wikipedia.org/wiki/Fresnel_equations
Raytracing
http://en.wikipedia.org/wiki/Ray_tracing_(graphics)
 How the Blinn/Phong Shader Works:
http://en.wikipedia.org/wiki/Ray_tracing_(graphics)
Yeah, it's math. Math sucks, but it'll help you understand the concepts. Because Lighting, and Texturing are practically one and the same.
And when you get a chance look up "Index of Refraction"
Also, I use 24mm for my focal length when I'm rendering. That, and don't be afraid to go into higher details in your mesh, learn to love the 'bevel'. 
Also, also. I personally 
HATE booleans, with a passion. I hate them more then Khan hates Kirk. I'd avoid them at all cost, I would rather crash geometry unless I have no other choice, unless the circular window is in your face. Stick with a normal map.
Last thing, on azteking? Use multiply on the layer and reduce the opacity to 9-12% on the diffuse map, 30-50% on the spec 
 
 
I think that's it...hmmmmm. Oh well, that should be enough to get you started.
If you want pictures I can show you some stuff, and how I do it.
Good luck 
