Way beyond a list of low-emitting furniture, there's a whole green building database on Scientific Certification Systems' website here: http://www.scscertified.com/ecoproducts/products/

Find curtains, rugs, and paint to match your new green furniture! All products are certified by SCS as meeting the highest levels of environmental performance, whether indoor air quality, recycled content, or using FSC-certified wood. for more info, visit http://www.scscertified.com

I've worked in the contract furniture industry for the past 3 years, and I'm now the Sustainability Coordinator for my company.  I agree Umbra, GreenGuard is a great resource for low-emitting furniture, but just because it doesn't off-gas doesn't always mean it's sustainably manufactured.  Mary Beth, you should check out http://www.sustainablefurniturecouncil.org.  They have a great listing of member companies and their websites.
Another point to make regarding the upholstery, there are some GREAT recycled polyester fabrics on the market now that are sturdy enough for commercial use.  Check out Interface Fabric's Terratex line (http://www.terratex.com) or Valley Forge's FRESH line (http://www.valleyforge.com).  Many furniture manufacturers will give you a COM option (customer's own material), so even if the manufacturer you go with doesn't offer "green" fabrics you can purchase it separately and send it in for upholstery.
Hope this helps!  (And if you need stackable chairs, check out my company at http://www.mtsseating.com!)

How about those rustic and log furnitures? Have you tried western leather furniture?

I found a good furniture store  online recently that I think some will find interesting. It is called BestpricedFurniture with complete list of modern furniture.