What I would like to do is overlay topo lines and markings from an old map onto an arial photo of an area. Could someone tell me an easy way to do this without purchasing an expensive software suite?
I'm more familiar with Photoshop, an expensive image editing program, but GIMP will also do it, and can be downloaded for free. It's kind of a steep learning curve, and I'm not going to give you step by step instructions as I don't know all the specifics of that program, but essentially I would open the photo and overlay the old map as a new layer. Reduce the opacity of the new layer to about 30% so you can see the photo (background layer) through it. You will probably have to adjust the map for orientation and scale, select 2 or 3 points that can be identified on both layers and adjust so that they line up. You can, if desired, add a 3rd layer and mark points of interest at 100% opacity. Now you can make the map invisible and you have a photo with markings on it.
