Technical books. I started writing in 2011. After a few books I was able to do look during launches but sales fell dramatically after. Now I have a couple boo

Technical books. I started writing in 2011. After a few books I was able to do look during launches but sales fell dramatically after. Now I have a couple books doing $2k / month. Since I do corporate training I have probably made dramatically more than this from the marketing from my books but don't really have a way to track that. https://store.metasnake.com/ https://store.metasnake.com/