Cycles is blender's newer render engine that is fully raytraced and can easily create realistic results. On the other hand the older blender internal renderer can give you more control over lights, like length and angle from source but also the ability to subtract light from areas, it also supports volumetric rendering (if you want a foggy lit area) which is being worked on for cycles. This may be a key to the results you want. As you want to have control over the area that is lit I would run a couple of tests with lights over a plane to see whether cycles or blender internal can easily give the results your after.
As for the final render you can set the camera to perspective with control over focal length or orthographic and adjust scale as well as the option of a panoramic camera to get the final image you want.
Blender includes a ruler and protractor feature, there are also a couple of addons that may help. The scene settings offer metric or imperial display of measurements within blender.
For concepts, it sounds like your final scene would be fairly simple and any basic modelling and texturing would help. Blendswap could be a good resource for free models to help get you started.
For tutorials Blender Cookie is a great site for tutorials on specific tasks and has a good introduction to blender tutorial, while Blenderguru tutorials focus more on the final image.
Blender has also had it's own stackexchange site blender.stackexchange.com for a few months now.