Police say the new Horsewatch Northants scheme is similar to Neighbourhood Watch, and encourages horse owners and those in the industry to work together in local groups in partnership with the police.
Chairwoman Rebecca Hall said: "We decided to set up Horsewatch Northants in order to help in the fight against equine-related crime.
"As well as reacting to incidents, one of our main aims is to encourage people to take security precautions to prevent them becoming victims of crime in the first place.
"If people look on the site they will see a number of simple measures that can be taken. It is important to mark your property."
Horse owners can register details of their horses via a website – including pictures, descriptions, distinguishing marks and microchip numbers – and these details are quickly circulated to other members in the county and nationwide in the case of a theft.
She said several horses had already been recovered as a result of the scheme.
Horsewatch Northants is free to join but small donations to cover website and administration costs are welcome.
Northants Police wildlife officer Glynne Malkin said: "This scheme will be of great benefit to Northamptonshire's equine industry.
"Fortunately, at this time equine-related crime within the county is fairly low but we are keen to work in partnership with Horsewatch to make sure that trend continues."
She asked owners to ensure all riding equipment is permanently marked, so it can be returned to them if ever stolen and later recovered.
Secure storage is also vital, she added.
Horsewatch Northants is a voluntary non-profit organisation, funded by donations and sponsorship from local businesses. Visit the website www.horsewatchnorthants.org.uk, or contact the Horse Theft Helpline on 07968 762192 for more information.