Well, it seems that http://read.kitabklasik.co.cc/ has done half of our work for us. They have uploaded a gigantic list of excellent books (with many being the best editions) on their website. Granted, the books are all in Arabic so the English-speaking readership of this site will benefit less from it.
For the seeker and scholar, however, this is a treasure beyond praise. In the future, when uploading books, we will try to first check and see if the book can be found on KitabKlasik. If not, then we hope that our contributions will add to larger sites’ databases.
We are also trying to add a link bar on the side of this site which will list the best websites for finding books online.
Ṭaḥāwī 
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