link: http://www.filterforge.com/filters/
Select ‘All filters by category’ and there will be different categories to choose from like organic, buildings etc
Those are actually some filters for Photoshop plugin, but as far as I tried they are also perfect for texturing models lol. There are about 8k of them in total :o
the good thing is that if you make your own filters (even with trial) then you can get reward points, with which you can get the full program for free.