I have been suggested to write this post to point your attention to a free software i'm being developing for automatic image (and 3d model!!!) georeferencing.
It is called AutoGR-Toolkit and it is based on image matching. It provides thousands of ground control points in seconds. These points can then be used in ArcGIS or QGIS (for 2D matching) and also in Agisoft Photoscan, VSfm or sfm_georef (for 3D model georeferencing).
It also gives the possibility to download high-resolution orthophotos from freely accessibly WMS server.
It is free and it will stay free of charge, but I need your feedback to improve it and make it more useful for you too.
If you think you are interested, please feel free to visit www.ims.forth.gr/autogr and download the last version of AutoGR-Toolkit.
Looking forward to hearing from you!