It gives info on shipping MEDIA MAIL, which is books & albums, as opposed to PRIORITY MAIL.
If you have an item under 13 oz, there is FIRST CLASS MAIL, great for small items, such as nic-naks, some jewelry, etc...
These services are great ways to ship, except it will take up to 5-7 days, sometimes more.
You can't use a priority mail box for these services, you will have to use your own box.
Stores such as Walmart, Target, etc., are great places to find boxes when they are stocking
shelves, and are more than happy to let you have them.
Another added benefit to using USPS, you will be helping to preserve an Icon, as using their
service will help keep them alive into the distant future :)
Also another resource that may help
USPS SHIPPING CALCULATOR
SHIPPING LARGE ITEMS/FURNITURE
One that ships internationally
This one takes bids for your business with various movers, so you can get the best price.