Perhaps the Green Boroughs Walking Tour of Park Slope green businesses would be of interest? It will take place on Sunday, July 27. Per an email:

The Green Boroughs Walking Tour of Park Slope will take you to the newest, coolest, greenest retail stores, green buildings, community gardens, parks and other green places in Park Slope! Meet the Brooklynites, including the designers, architects and “Greentrepreneurs” who are helping to make Park Slope one of the greenest parts of New York City. Touch, taste, and try on green clothing and other green products. You can’t do this on-line! The tour will start at 1 PM and conclude at about 3:30 PM. To reserve your spot for this tour or any of the Green Boroughs Walking Tours, call Les at 718.530.5074 or e-mail _Les@greenboroughs.com_
(mailto:Les@greenboroughs.com) today!

The cost is $25 per person; $15 for full-time students.