Hi Cindy. You can shut the water off to the hose bibb. The valve should be near the water heater, underneath a sink or an access panel. Put a picture on Hometalk so I can take a look at the type of hose bibb that you have.
If you can - unscrew the whole thing and take it to hardware store or big box and have them match it up and replace the entire hose bib. They are not expensive.
I would look for a shutoff in the basement and shut it off there when you want to. Otherwise, you could screw on an additional shut off on top of your existing hose bib.
Attach a hose with a hose nozzle on it, which can then be twisted to the OFF position. I'm with Vincent though...they are pretty cheap to replace. :)
Agrees with Arrowhead and Vincent Plumbing
Cindy: I would take a pic of your faucet you wish to fix, go to Lowes or Home Depot with pic and get parts required and ask them how to fix. They should have someone on their staff to help you. Good luck
Have you even gotten a quote from a plumber?
It mostly likely new a new washer inserted.