As of 2015, a good location to purchase inexpensive self-leveling compound for a concrete floor is Lowe's. Available compounds and prices can be found using the search bar feature on the website.
Products can be purchased online or in store. The nearest retail location can be found using the store finder. Weekly ads and specials are also listed on the site.
Another location for finding inexpensive self-leveling compound is Home Depot. Products can be purchased online and shipped or picked up at a local store. Home Depot stores also offer price matching.
Watco Floors is another location where self-leveling compound is sold. An online catalog can be requested for free.