Mando,
Dicksmith or Electronics are us, stock loads of that gear but will require a crimper or soldering iron.
Farnell components (
www.farnell.com) have loads of great stuff and if you don't want to buy over the net any L&H, mm electrical store or the like will be able to order what ever you want. Stuff like 'p' clips for mounting your looms, flexible conduit or spiral wrap for wrapping up looms can all be found.
Give me a ring if you need help.
Talk to you soon Gav