Putting my flame retardant suit and my book-sellers hat on at the same time ...
I sell books on
Amazon. Lots of books. At Amazon, the time estimate for media mail is 4-14
business days. I am sure that Overstock.com also specifies business days: Monday - Friday counts only, Saturdays, Sundays and Holidays do not. You cancelled your order exactly on the 14 day mark. In addition, that is really just a time estimate. Media Mail can be fast or it can be very, very slow. It is the last service of mail to be moved ... and only if there is room. Bags of media mail get "stuck" along the way. I have had books take literally an entire month to reach their destination (according to my delivery confirmation). I have had the post office lose books.
You didn't say, did the book ever arrive? If it did, then I think that you jumped the gun on canceling your order since it was obviously stuck in transit. Now, if they didn't
ship in 14 business days, then you have a real complaint.
In the future you should find the ISBN number of the book you want to buy and search Amazon and
www.addall.com. You will want to select a place that will expedite your book to you (usually USPS Priority Mail) so you get your book quickly. If you buy from Amazon, try to pick a seller with at least a 4.8 rating. The lower rated sellers have a lot of problems.
FWIW, I almost never choose "standard" shipping on books from the Amazon Marketplace myself because I know how long it could take. I would certainly never do that with a textbook that I need for class!