University of Toronto (Canada)
Harrison/special Theory of Relativity
This page provides an incredibly detailed description of Albert Einstein's Special Theory of Relativity. Definitely an excellent website with great pictures and examples!
Bartleby
Bartleby.com: Einstein "Relativity: The Special and General Theory"
This page presents the actual text of Albert Einstein's book "Relativity: The Special and General Theory." Just click on the chapter titles to read the text.