Tutorial 

Siemens Automation Cooperates with Education (SCE) provides tutorial materials on Siemens S7 in the following link:

Animation/Flash

The following is the presentation on Siemens PLCs for begineers:

The following links are flash animation of Siemens S7 (right click to download):

The following link is the demo system for Siemens PCS7 (right click to download):

s7-300-2342

Books

Several books are available for good sources for studying Simatic S7 (note that the following links only provide the sample pages):

books

Master’s Thesis

The following link is the Master’s Thesis about Siemens S7 application:

The following links are the Master’s Thesis about Siemens PCS7 application:

Further References