As you can probably tell from the title I want to secure a set of ladders to the side of my house - it's got to be done so that a thief doesn't have any easy time of it as this is now the third pair of ladders I've bought the other two sets being pinched from inside my shed. Any ideas or anyone that can do the job please?

I think Screwfix do an appropriate kit

Just remember not to fix it vertically next to a window or roof. This just gives them an easy route into the house.

I dont know if something like this would do -
http://www.screwfix.com/prods/48323/Ironmongery/Hooks/Storage-Hooks/Ladder-Bracket-Black-170mm-Pack-of-2
Looks like there is a way of padlocking the 2 parts together to secure the ladders.
Hope this helps.

(BTW, I have some paving/fencing brochures to drop in at some point)

you will need some sort of system that prevents the theivs from just unbolting the whole lot too, like the way a paclock bar works, using to bar to protect the fitting.