The striped fabric is outdoor fabric purchased from fabric.com and the pillows are outdoor pillow inserts purchased from there as well. I figured I better get the materials appropriate for outside since I wanted to leave them out there all the time. It helps that they are on a covered porch which limits some exposure to the elements.
NOTE: I am a big fan of fabric.com. The samples are reasonably priced (only $1.75) and they are large in size. I also like their "Design Wall" feature where you can look at the photos of fabrics side by side. They also have quick shipping and great customer service.
The tie was created by sewing a strip of fabric to the back of the pillow fabric before sewing the pillow together. It's not rocket science, but without the ties we would have to worry about the pillows blowing away.
The chairs are a "Polywood" material. They make these things out of 90% post consumer waste! In addition, they are made in the USA. We were considering wood chairs, however, with the proximity to the Gulf and the salty air - we were concerned how quickly wood might deteriorate. After asking around - it seemed Polywood was the way to go. The price was worth it for durable low maintenance chairs at our beach cottage. It is also nice that they are on the heavy side (similar to a chair made of wood) so that we don't have to worry about them blowing away in strong winds. I took our friend's advice and put a coat of car wax on them to make them even easier to clean and resist mildew. We purchased the two Adirondack chairs, the small table and a porch swing from this website.