They are called Bubble Chairs
Yes, umbrella chairs, inflatable chairs, etc....
Yes, Ebay.com does sell office chairs. There's a manufacturer called Spider Office Chairs that sells them. Here's the link (http://stores.ebay.com/Spider-Office-Chairs).
No they do not, but Office Depot does sell Herman Miller chairs. They have a wide variety of office chairs to choose from. http://www.officedepot.com/a/browse/chairs/N=5+501503/
Best Buy does sell mesh office chairs. They offer several colors and brands. Chairs are available online or in stores.
Simmons Furniture does sell single dining chairs. Simmons Furniture has a large selection of chairs for different purposes, which can be bought as a set or individually.
Many department stores sell bedroom chairs, however Walmart, Target, and JcPenny would offer the cheapest and best quality(for the price) bedroom chairs.
Staples does sell ergonomic office chairs however their range is not that large. These chairs are available at similar prices, and sometimes cheaper, from stores such as office depot.
Well one way would be to look for bubble gum under chairs and desks or on the pavement/sidewalks.
Knoll, a furniture website, sell a variety of chairs designed for many purposes. The colour of chairs available in stock include: black, red, white, brown, and blue as examples.
ikea does sell bean bags
Yes, Ethan Allen does sell rocking chairs. They sell different styles of rocking chairs. You can buy a used Ethan Allen rocking chair for around $125. Brand new they typically cost around $250.