Lighting looks good

But crop or zoom in more on the building. Also you might just want to elevate it on a table and shoot photos that way. Building looks great btw! 

You need a "fill reflector"

You need a "fill reflector".

How to do it: Next XL pizza you order, save the box. Or use a pizza pan if you have one, or the side of a box a TV or microwave came in. You want a piece of cardboard at least 18-24 inches square.

Cover the cardboard/whatever with aluminum foil, matte (NON shiny) side out. You could even paint it with silver (or white) spray paint if you want a little less reflected fill. Put the reflector on the "dark" side of the model, in this case, the left side as you look at the photo. Aim it to reflect light back at the dark side of the model. Now get in close, and fill the frame with your model. This isn't "art" photography, you're not looking for the rule of thirds here. What you want is a clear, well-lit picture that doesn't have bright sports burned in, or dark places you can't see detail. If you can still barely see the shadow, it's just about right. If you see YOUR shadow, move and shoot again.

Your real issue is going to be lenses. If you're lucky, you'll have a decent depth of field. If you're not lucky...  well, you'll have to take most of your pictures "straight on" for the detail you want to show. More light means, in most cases, you can get close to the maximum depth of field your camera will manage... with a traditional film camera. Unless you've spent a load of money for a digital SLR, things can be... interesting.

"Enough light" is the point at which the plastic doesn't quite soften.

Don't think for a minute you can't cross that line with only sunlight.

Finally, take a LOT of photos. Then take some more. And some more. And then start over and repeat them all.

The real thing that digital photography has done for the masses is that it's made it possible for them to take enough pictures to actually begin to understand photography without putting them in the poorhouse. I shot more photos in the first 3 months with my first digital camera than I had in my whole LIFE with film.. and when I went back to the film camera for a specific project, the new skills I learned carried over. With digital, there's no such thing as "too many photos"... they're basically free, and the media is reusable. Go wild!

An alternative to sunlight

Pick up a couple of cheap reflectors at your local big box store, then go to a real photo store and get a couple of "color balanced bulbs".  Said bulbs used to run about 8$ per (they last a long time, due to limited use, so I haven't bought one in 10+ years).  Put the bulbs in the reflectors and aim the reflectors at the 2 sides of the model.  If you want to get fancy, you can remove the clamps from the reflectors and get stands, but that costs more.  Adjust the location of the reflectors until you remove unwanted shadows.

For a background, use either a pastel pillow case or a sheet hanging from something like a bookcase.  Now all you need is a small table for underneath the model. 

As an old film photographer, I used to say that a good roll of film was 1-3 good shots on a roll of 36.  With digital, the number is even smaller, but you can shoot all day.

Do you have ?

Is there a close-up setting on your camera? Usually these are marked with a pictogram of a tulip. If you can use  aperture-priority, put your camera on the A setting and dial in the highest numerical f/stop you can find -- probably something around f/22, f28 or something like that.

You will be getting into long exposures with these settings and will need some way to hold the camera motionless.

Here's a rough illustration of a basic set-up with a small camera on a flexy mini-tripod and two desk lights. You'll have to do color balance corrections in something like Picasa. You'll also want to clean up the messy background . . .

Mycroft mentions bulbs.  If you root around at a hardware store or lighting shop, there are compact fluorescent bulbs rated for around 5100 K  light temperature, which is close to the wavelength of daylight. CFLs don't heat up and won't melt plastic and resin models.

Cheap Light Box

You can also build a very inexpensive light box like this:

http://strobist.blogspot.com/2006/07/how-to-diy-10-macro-photo-studio.html

I built one like this and used an inexpensive utility light with a "daylight" 100w equivalent cfl. That coupled with discovering the macro setting on my cheap Fuji S1500 camera increased the quality of my photos tenfold.

http://www.walmart.com/ip/Bayco-8.5-Clamp-Light/14003467

Sometimes publishers don't want you to modify your photos for color correction, they have pros on staff that know what works best for their format and will edit your originals accordingly. Check with them or provide both the edits and the originals for them.

I have ideas for a couple of short articles

 I read articles for the ideas so the photo quality doesn't matter to me as long as I can see what the author is trying to convey.  The simplest changes I can suggest would be to set the model on a plain white or other solid colored background instead of the grainy look of the concrete and then crop it to just include the model or the features on the model the article is about. If you want to do an article and can't get it accepted to a magazine you can always just post it as a blog here and lots of folks will still read it...DaveB