create/convert materies/textures into hammer
http://www.youtube.com/watch?v=I3KdPDQjmvg
This is what I was looking at doing. This gives me a very good feeling of the building, with the greatest interactivity. Very nice video, thank you! This video has pointed me in the direction I want to explore.
Theres a reason I want to explore this. I have 4 1/2 years until I'm out of school. So I have time to explore. This is an option I haven't explored yet. Drawings, physical models, and 3D modeling programs are well talked about already. Next, I'm not interested in what would be used in a company, and nowhere in my first post, did I talk about profession. Just about textures. If we are to talk about it, there are a lot of other points that can be brought up. I know many architecture firms that use programs as simple as SketchUp for thier renderings and design. In this case quality of the render is not as important as representation and exploration of the model. I introduced 3Dconnexion to an office, and now they use it for showing models to both clients and contractors. So theres a whole spectrum of things to use, and this is just one I want to explore and learn more about.
Thanks for the help everyone. I'll try those steps to convert the materials.
I would still recommend talking to instructors about this, it would be a shame to learn lots of hammer to just have a professor tell you no. As for what profession, I would recommend treating your studies like a job, just because you're not in the industry yet doesn't mean you shouldn't learn the tools they use. It sounds like a fun project, if your professor likes the idea of a game engine then great! But the buck stops there. After all, a school isn't going to teach you programs that wont be allowed later.
As for 3dconnexion... thats a device designed for drafting. Steam is a game engine designed for games, I don't really see the connection.
I personally would rather use a professional 3d app. You dont have to worry about leaks or entities. No hint brushes or area portals. Better control of lighting and textures. The only poly limit is based on how long you're willing to render...
I am just trying to give constructive advise, of course im an animator not an architect, I'd suggest talking with your professors about it, they should know more 
I'm doing this for my own interest, not for the school or instructor.
I find people can be very open to new ideas if there is a good use for them. I was saying that at my last job, despite how much hand-drafting we did, we used SketchUp and 3Dconnexion as presentation tools. This is neither drafting, physical models, nor animation, but it turned out to be great for for both contractors and clients to better understand our designs. I think hammer can be a good tool as well because of the navigation. The thing I don't like about animations is that one loses a lot of control. I find that during animation presentations, people are always asking 'what was that over there'? and then you have to say 'wait.. let me get back to that part of the movie.' and then proceed to fiddle with it and try to show them. I'm especially looking at portal because you start without any kind of HUD nor gun, leaving a 'clean' view. But I think that can be done in others as well.
Try loading Kasperg's cs_fallingliquid, I loved exploring that, and got way more out of it than the video, or other pictures of it that I have seen.
my own interest and interactivity are the driving points of my reason for using hammer. Thats all.
Does anyone else have anything to add to getting different textures in?
I am also wondering where I can get more entities as well. I don't even have plants, which my building is desperatly needing.
Thanks!
look for different models for foliage, use a prop_static...
thats cool its for personal interest. I see what you mean that they can walk around and look at their building, but that also takes time. Many people would rather see a well done 2-minute animation than walk around for half an hour. I can see where both can be useful tho. There are model viewers that allow you to free rotate and walk around models, that might be more what you're thinking of since it wouldn't be as restrictive as a game. I'm sure you'll get to stuff like that in your classes, until then it can't hurt to make them in portal, especially if you plan on making some maps to share with the community 
one thing I do not like about hammer, is how you can't edit materials, without extracting them, rewriting stuff, recompiling them, and them dumping them into a folder. It seems more like programing than art, and I think texturing is an art not a science. but if you're looking for some good textures, look into Total Textures they're really good, they have lots of architectural stuff and its royalty free. anyways, good luck