There are many great stores that sell outdoor folding chairs. Ollie's bargain outlet sells a great deal of folding chairs for the outdoors in the spring and summer seasons. You can find these chairs year round at Dick's Sporting Goods.
The best place to find cheap folding outdoor chairs would be at Target. They have an amazing selection in the garden section.
Craig's or Salvation Army if you can wait for them to pop up or you can rent as many as you need.
Plastic folding chars are an excelent choice for outdoor use, as they are cheap and easy to transport due to their size, but generally are very stable.
Some places where you can purchase cheap outdoor patios are: http://www.patiolivingandmore.com/ and http://poolandpatio.about.com/od/decoratingoutdoorspaces/tp/inexpensive_patio_furniture.htm
You can purchase a new cheap patio chair the matches any decoration at Target, Home Depot, Walmart, and Kmart. At these stores, the prices may vary, but they generally have cheap patio chairs.
Cheap chair covers cost about two dollars to purchase. The cheapest materials to look for in chair covers are satin and polyester, which still come in many colors.
I would use Amazon or EBay for the purchase of outdoor dining sets there are several different kinds of outdoor dining sets to chose from. Some are cheap and some are pretty expensive
One of the things to look for when choosing cheap outdoor chairs is what material is inside of the chair. Chairs that have wicker or other woven materials on the outside should have a steel or rattan frame inside of the chair. A chair that has a frame that is made from wicker, aluminum or wood will most likely break over time. The material that the frame is made from can almost always be seen by looking at the bottom of the feet of the chair.
Lifetime folding tables can be purchased in bulk through the Competitive Edge website. You can purchase a 24-pack of 37" Lifetime tables for $1294.26.
you can purchase an executive chair direct form the manufacturers, but I recommend your local office depot or staples. I think you will find better values at Wal-Mart where you can get a chair as cheap as $50
There are outdoor market umbrellas at ikea. Also available on Amazon.com. They will be great for outdoor markets and are very cheap usually. Amazon is the best place for these umbrellas.
A cheap, used bungee chair could be found online at Craigslist or E-Bay. New chairs could be bought on Amazon and Target. Prices seem to be $85.00 to $200.00.