This page is a compilation of online resources on residential windows...
Guides, Catalogues and Documents on Windows
Large window manufacturers have a wide range of information (catalogues, technical information, window installation...) on their products. Take a look at their sites.
Below we list four good online guides and documents on windows:
US Department of Energy Selecting Windows for Energy Efficiency
US Department of Energy Energy Savers, Windows
Energy Star Efficiency Windows: Performance criteria and USA climates zones
Natural Resources Canada: Buying Guide to Energy Efficient Windows
Finding Window Installers
Retailers and big improvement stores can assist you to find windows installers.
In the USA, you may find certified professionals in the Resnet database: Resnet Window Repair.
Also in USA, the U.S. Department of Energy's Weatherization Assistance Program help low-income families to find certified professionals. See: State weatherization contacts.
Weekend DIY Window Projects
For help on weatherstripping window projects you may take a look at...
Weatherproofing your windows with vinyl V-strips (Home Depot)
Weatherproofing casement and sliding windows (Home Depot)
Weatherstripping around windows and doors (Home Depot)
Though with a wider scope, professional energy audits can also involve the windows. If you intend to consider this type of audits, see:
Window Sizing and Placement