Just an information source link (discovered while looking for something else):
http://pubs.usgs.gov/publications/text/dynamic.html
This is a United States Geological Survey (USGS) online publication, covering plate tectonics.
The full title is
This Dynamic Earth: The Story Of Plate Tectonics.
Please note the text info, towards the bottom of page. Book is available in a number of forms, including .pdf file.
Moose