Here are some links…

[jb]

Here are some links I found using a power search on metacrawler.com:

http://hansenwholesale.com/fireplaces/glass_doors/glasdoor.html

http://www.looksmart.com/eus1/eus53671/eus158347/eus227510/eus578466/eus235843/eus565314/eus581148/r?l&

http://www.fireguardglassdoors.com/

http://www.mantelshop.com/glsdrs.html

http://www.house-of-fireplaces.com/hearthcraft/

http://www.diamond-w.com/diamond/

Your fireplace will be about 85% more efficient (with glass doors vs. without) because you won’t be sucking all your house’s heated air up the chimney.