You can get blank DVD box cases for your backups from
www.bigpockets.co.uk or
www.blankdiscshop.co.uk for a very reasonable price.
With regard to the cover question, there was some debate on this forum some time ago which ended in a request from one of the main men of the site to not post links directly for cover sites. Charlie/Tyler (even BG as I remember
) correct me if I am wrong, if I'm not perhaps the forum rules need to be updated...