TheLogoDB.com came about during the development of the live tv Kodi feature.
We needed a programatic way to search for and download various tv logos from around the world.
At the moment there is no automated way of adding channels, but feel free to email me: zag (at) kodi.tv to add any new channels to the packages. You can also write on the kodi forums in the specific logodb thread.
Simply go to the channels page via a search, and click the big red button. Make sure your logo is of good quality in PNG format with a transparent background. The dimensions needed are 800x450.