Photos from my web-site pop up all over the place on the internet.
For instance, someone selling Poncirus trifoliata seeds on ebay under the name 'Exotic Garden' uses my pictures.
On the other hand, I have been contacted three or four times by publishers or authors requesting higher definition versions of my website pictures. They have paid to use them in their books.
One Australian nursery asked to use images on their plant tags. They sent me a few of the tags and a packet of seeds in exchange!
I always allow non-commercial organisations to use pictures for nothing, provided there is acknowledgement.
Mike aka Citange
www.homecitrusgrowers.co.uk