A good place to start would be your local Yellow Pages or classifieds, though nowadays it's not that hard to find contractors online (many advertise on local auction sites, have their own domain). Word of mouth is still invaluable though, you can also ask around, at work or in your neighbourhood to get some recommendations, even Yelp can provide reviews on professional craftsmen.
Generally you just ask the contractor if he's insured, before hiring them.
You can find information about how to get a contractor license on the following website: http://www.contractors-license.org/cna03.htm. They have a lot of useful information.
To find someone to do kitchen repairs I would call a local contractor.
"T&R Fence & Deck" is a small company that can install a pool fence for you. Their local number in Toledo is (419) 478-0629.
You can find information about about what is needed for a contractor license in Colorado on the following site: http://www.contractors-license.org/co/co.htm. They have a lot of useful information.
Kiewit currently has a hydro dam in brazil
You want to find an electrical contractor that is in the union. This means that he has passed the appropriate tests and is well-prepared to work for you.
One can find information about hiring a cottage in Wales on websites such as Wales Cottages, Holiday Lettings, Home Away, Cottages Direct, Sykes Cottages and Stay in Wales.
Fencecompanydirectory.com is a great website to find a fence company in your area. They give you access to local fence companies and their websites to give information on installing new fences in your yard.
One can find information on hiring a security officer by inquiring their past employers, (seeking out references) and looking through data bases with track records of individual employees.
Your state government will have a contractor license bureau. In order to become a licensed contractor you have to meet the state board's requirements. For specifics you'd have find their website.
You can find out about a job at Gliders by visiting a location or by checking out their website. Their website has information about hiring and applications.