If you want to add any of them, make sure you own the copyright. If you don't, you will be suspended.
~Callum
If all goes well and you DO own the copyright and have NOT STOLEN the content from anywhere. Meaning it was MADE BY YOU, then you can upload the files to your cpanel file manager directory. For example if i add a PDF file (ebook) named myebook.pdf and upload it to the home directory on the cpanel file directory then your URL to download it would be
http://www.yoursite.domain/myebook.pdf. Basically all you have to do is upload it to the directory.
Edit:
Terms Of Service
"File Storage: Accounts are not to be used for file storage, your account will be permanently suspended if found to be breaking this rule. Downloads are only allowed on your x10Hosting account if they have to do directly with your website. e.g. you developed custom software and are selling it or giving it away. Accounts may not be used for mirrors, game file hosting, or any other type of file hosting not specified here."
This means do not use copyrighted material or anything that would break the tos.