WHERE TO BUY

Porch gliders can be bought from various places. Places such as your local furniture store will most definitely sell these. If you are lazy and would much rather prefer to purchase it online then you can also do that. Purchasing online is not a bad idea as you are given more options on what to choose , some companies even sell porch's exclusively.

There are various sites online that you can purchase porch's from including : 
Amazon

Ebay
Overstock

Wayfair

Purchasing porchs online will cost you a little more, in some cases some companies will charge you for a delivery fee. A delivery fee may range from anywhere between a few bucks to a low hundred dollars. Some companies even offer free shipping which is quite generous of them. I personally like to purchase porchs myself in person, this allows me to estimate the size as well as check the quality. You don't want to be purchasing a porch online only to have it damaged when arrived, this will be troublesome to fix and replace. Purchasing it yourself in person is a much better way to avoid this hassle and trouble.