You may also search AAMA's online Certified Products Directory at http://www.aamanet.org/CertifiedProducts
. It will be helpful to know the name of the actual window manufacturer since that's how the AAMA directory is set up. You can search the directory by manufacturer, not by the name of the window dealer who sells the windows, though in some cases that could be one in the same.
To clarify, the NFRC certification denotes thermal performance. AAMA offers an additional certification for air, water and structural performance, in addition to forced entry resistance testing. Just so you are aware, AAMA certification is a step up from other window certifications. AAMA is the only program that performs two unannounced plant inspections each year. Others may do these inspections, but they give advance notice. It's a lot easier to clean your house when your know company is coming!
To ensure that it is AAMA certified for air, water and structural performance, check for a gold label with the AAMA logo on the left. There are many copy cats, so it's important to check for the logo. If the label has the logo, but it's silver, that means that AAMA has verified the testing of the product to NFRC's thermal standards only.
Learn more about AAMA certification by visiting http://www.aamanet.org/general/1/32/certification
. And, good luck!