The ebook you bought should have a Smart Media card already installed.
What you need to upgrade is a card reader that can handle the Smart Media. They are out there but you may have to order one online, I doubt any big box store would have one. You may find one at one of the little computer stores.
Once you find a reader you can download the files from http://www.ebooktechnologies.com/migration.htm
You may want to email eBookwise to see if you actually need to upgrade or if you can just "refurbish" the reader and then sign up at eBookwise. Refurbishing will remove the prior owners data and allow you to make the reader your own.