Is it close to your house? We put in a Yale alarm system that works remotely and covers two sheds, the tack room and our lounge with the alarm control in the house alongside an alarm box that flashes if activated, we have turned the bell box off on it. If activated it calls both our mobiles.
Unfortunately because many yards are in isolated areas many intruders just smash there way in leaving the alarm ringing while they remove property knowing that it will be some time before anyone can get there.
Ensure that all your tack is tack marked with your post code and all your equipment marked as well. One of the best products to use is Smartwater. www.smartwater.com. as once the product is handled then anyone coming in contact with it will be contaminated with the unique coded micr-particles.
You can mark your own tack using the Rolson 38b piece automatic number & letter stamp set Item Number 26138.
A lot of stolen tack etc. is recovered but because it is not marked it is impossible to identify the owner.
Also ensure that all horses are freezemarked on a part of their body that can be seen while the horse is being ridden. i.e. not under the sddle area.
Also ensure that you subscribe to your local Horsewatch monthly newsletter (U.k. horse alliance) as this will keep you up-dated on any activity in your area.
I used a padlock alarm on a steel box that contained my energiser & battery. It's supposed to activate when the lock is moved/disturbed. It worked for a while but then failed, I changed the batteries but it made no difference. Assuming they work ok you have to think if they are suitable to use in the location you want to use them. An alarm is only any good if it is where someone is likely to hear it? I think this was the one I used:- http://www.amazon.co.uk/Padlock-Sec...icycles/dp/B0012EO3LU/ref=tag_stp_s2_edpp_url
Smart water & identifying marks on property is fine providing the property is recovered & then it can be returned to the owner. However a high percentage is never recovered. I believe it is better to spend time & effort in making the building you are trying to protect more secure. Use thicker wood for doors, steel line the door etc & generally make it so difficult & time consuming to break in that they will give up & go somewhere else.