As a membe of The Geological Society of London I use regularly the library map loan service. Any member can visit the GIS interface and search map in their area of interest. Then, email to the library and they will send by post the map.
There are many maps at many different scales from virtually everywhere. It is relatively fast (the time that takes to receive the maps with the mail), and if you can scan it, then you can georeference it in any GIS software (TNT, ArcGIS), or some geological software (Move, Kingdom Suite, etc).
In these days, we forget sometimes that there is a vast amount of data in printed shape in libraries and geological societies and clubs. This data is not available in many cases in a digital format, and most of people just ignore its existence.
But if you are managing a project, you want to get as much data as you can, cheap, and easy to use...
So don't forget to check the old paper maps for your next project!