On the web you may find text, images, video, audio, games, learning objects, and any other kind of content you can imagine.
The most important thing is to determine whether the item was posted on the web legally. You can't get permission to use an item from a person who themself pirated it!
A lot of the content on the web is unattributed and has no contact information. In these cases, it's impossible to get copyright permission.
If you can identify the correct copyright owner, all you have to do is contact them directly, usually by email. However, many of them are unfamiliar with how copyright works. On one hand, they may grant you permission right away without any restrictions or royalties. On the other, they may decide that it's too intimidating or risky, and just say no.
Also, many other countries have "moral rights" (having to do with privacy, libel, etc.) in addition to copyright.
We recommend contacting by email or phone first to confirm that they are the right person to ask, and to determine whether they wish to proceed by email or land mail.
If you are using land mail, be sure to enclose a self-addressed, stamped envelope, and send it all by Certified Mail so that you can be sure that it arrived.