Resources, Links
Standard Documents
Smart cards are defined in ISO 7816 standards. You need to buy those from ISO, but some pages have overviews on what is in those standards.
PC/SC Workgroup defines the PC/SC standard that is used on windows, but thanks to PC/SC-Lite software also on Linux, Mac OS X and BSD. You can download all parts of the specification.
The Multifunctioanal Card Terminal specification suite includes CT-API and it's co-specification CT-BCS. The whole suite is available for download in english and german.
Software
The M.U.S.C.L.E. project offers the open source software PC/SC-Lite and links to many drivers in ifdhandler format, and also to some applications.
Some drivers in CT-API format are available for download at Gregor's CT-API-Page.
OpenSC is a software to use cryptographic smart cards on Linux, Windows and Mac OS X. Developed by the same team as OpenCT.