Many sites have done a great job preserving printed materials of the past, and I'd like to point out a few. First, is the 1940s book How to Make Friends by Telephone scanned in its entirety here.
Next up is an amazing gallery of vintage romance novels featuring nurses. You wouldn't think there'd be so damn many, but there's over three hundred! Even better, the site not only has cover images, but a description and quote from every single one.