E-commerce

In the Management Information systems textbook, it covers e-commerce. I use e-commerce all the time and I think many people, especially students do. We make purchases for books, etc. How do you feel about the security of buying and selling online? I recently bought some books from a sister company of Amazon.com, called Abebooks.com and they are an international company based in Canada. After realizing this and finding out about hidden international fees, I felt a little uneasy, but my books came through okay. How would you feel about purchasing internationally?