Here are links to some websites which you may find useful!
The British Horse Society http://bhs.org.uk
The Shetland pony Stud Book Society http://www.shetlandponystudbooksociety.co.uk
Horse and Rider Magazine https://www.horseandrideruk.com
Pony Breeders of Shetland Association https://www.shetlandponybreeders.com
Horse & Hound https://www.horseandhound.co.uk/
Ecclesiastical Insurance https://email.ecclesiastical.com/click/ggno-4xx1-k9ni-l1pmn5/
http://www.nwcu.police.uk/ UK National Wildlife Crime Unit (NWCU)