This article will explain how to buy fiberglass cloth for use in personal projects.
First, figure how much fiberglass cloth you will need and how quickly you need it. If you need only a small amount of fiberglass cloth to do a repair, (such as a boat patch or auto-body repair) you can buy this material at a local auto parts or boat supply store.
Figure out what kind of fiberglass cloth you will need. If it is a heavy-duty application, you will want a cloth that is over "24 oz". If it is for a light cosmetic repair, 8-12oz fiberglass cloth will be suitable.
So you figured out how much fiberglass cloth you need, and its more then a just small amount. Do an online search for "composite material suppliers", and visit the various websites that sell fiberglass.
Call the companies directly and compare costs. Be sure to ask for details on on fiberglass fabric weight, width of fabric, and shipping costs.
Buy the fabric, and wait for the shipment.