Listen to this free podcast to learn about promoting your mushroom business.
Here is a link to the Podcast.
Here is an episode of Outside the Box that is focused on mushroom growing as a business, and how you can promote it online for free.
Also, here is a link that shows you the simple steps you need to take to set up your business fan page on Facebook.
A great free or low-cost tool to use to help you create graphics for your fan page can be found here.