Suggestion for list of e-book sources

Hi,

I looked for a place for feeback or suggestions, maybe this is it.

I just looked for an e-book in Germany and only found it as Amazon Kindle. However, it is available as epub in a shop that is not listed in Calibre, so I suggest it to be included: Buecher.de (it is also part of the consortium for the reader Tolino).

Kind regards,
Distel