Are there any presets around for better encoding of avi formats from 3rd parties?

What is it exactly that you need? Creating a preset is a relatively simple process.

Codecs mainly as .epr files.

http://help.adobe.com/en_US/mediaencoder/cs/using/WS2bacbdf8d487e582-30a3408e12f8ee21458-7ffc.html

Yes I am aware of creating custom presets but as the title says I would like to download already made presets.