We've used Eco-Spec extensively in our latest home remodeling project, and got a good deal by buying "in bulk" through the local specialty paint store. If you are doing a big job, make sure to ask about specials or "contractor discounts."
Also, as far as color goes - unfortunately, the pigment tints added to mix colors also (usually) add VOC's, in proportion to the "depth" of the color. Lighter colors will release less. In fact, I don't even think BenMoore makes an EcoSpec base for colors darker than a "2 base", which is about a middle tone. Beyond that, the tint would make its "eco" VOC status irrelevant.
Lastly, we recently discovered that Olympic Paint is making an interior latex paint with zero VOC's by label. It's not "green seal," but it definitely is "low odor" (the labeling on the can). We found it at Lowe's Home Improvement Stores. The price is about the same as standard mid to high end paint, so it's not really a deal if you have a specialty store around that sells the better "eco-paints," but if you live somewhere without one, it could be a good alternative. Plus, it can be purchased & mixed in quarts for small jobs, which many of the "greener" paints don't offer. Anyway.

For VOC free paints see the range from Sto of Germany. They have been tested to high standards and are not expensive.

Why Not Aquacoat? All The qualities and very safe too.... Drinkable as well. If you are daring

Try American Pride Paints and YOLO Colorhouse. They are all Zero Voc! They spread and look beautiful!!

At our stores in Los Angeles and Santa Barbara, we carry AFM Safecoat, American Pride, and Yolo. These are all great paints, both Low and Zero VOC.

Regarding the issue of colorant, our store uses Zero VOC colorants (most paint stores won't). So you can still get a zero VOC paint even in a rich deep color.

I am a paint contractor and I have been using Olympic Premium no-voc paints for about 2 years now. It was recently rated in the top 5 paints by consumer reports and is only about $17-20, which is by far the least expensive no-voc paint that I could find anywhere. I have been using this do gain bids because I am using a high quality paint that costs less and is great for your health. I have used a few others such as Sherwin Williams low-voc paints which was of a much poorer quality and almost twice the price, even after my contractor discounts. The olympic paint is only available at lowe's I believe, but well worth the value given the no-voc and high ratings.

When we review a paints VOC's and quality, what we don't see is the actual environmental foot-print of the manufacture of these products.
I am intimately knowledgeable in the manufacturing processes of the top 50 coatings manufacturers, waste streams are publicly available for all of them. Compare the accountability of their Stewardship of our most precious of natural Resources, drinking water and VOC's, Buy quality of life with quality paint:
SAN CARLOS, California – March 17, 2008 – Kelly-Moore Paint Company received the 2007 Northern California, Large Facility, ‘Certificate of Merit’ from the California Water Environment Association (CWEA) as the runner up to ‘Facility of the Year’ winner Lawrence Livermore National Laboratory. Kelly-Moore Paints was recognized for taking proactive steps to meet current environmental pollution control standards.
http://www.kellymoorepaint.org