i use the following ones on everything i have plumbed into my canister. it allows me to take everything off piece by piece since moving 700+ pounds of aquarium and such is quite a task. they come in a couple different sizes since the filters they're made for come in different sizes with different tube configurations.
Marineland Quick Disconnect Valve 2 Pack 1/2 Inch-Aquarium Filter Tubing if you go with these search around for better prices (including shipping) or to see if your local fish store stocks them... some do!
you can get other valves at any decent hardware store. ask someone who works in/with or understands plumbing and they should be able to help. take note of the id (inside diameter) of your hose and either bring it with you or illustrate with the rolls they have in stock. they should be able to get you a ball or gate valve (either will work for your purposes) with hose barb ends. it will not be a cutoff/disconnect though, yet it should be cheaper. the downside will be the ease of taking things apart.
also whenever possible get a hose slightly smaller than your barbs and heat the ends in boiling water to stretch them over the barbs. once they cool off they should never leak or fall off. as a matter of fact to get them off you may need to cut them in some cases. it does make for a no worry, leak free seal though.