|Unlock Forum posting with Annual Membership.|
Yes! If you go up into the Help Center and enter printable postage in the search, you should find the details. There is a fee, 0.43 a label I believe, that goes to cover the fees to the provider and a small amount to the site. But, yes you can print your postage here and then you don't need to worry about the 13 oz rule or anything, drop your books in a bluebox or leave them for your carrier if they take packages.
Welcome to PBS.