You can sell your ebooks through Amazon's Kindle program or Apple's iTunes Connect, which gives you access to a large majority of the digital-book reading market and the barriers for entry are incredibly low. You don't need to invest lots of money to make this happen, but you do need to invest lots of time, not only in writing the ebooks, but in marketing them as well.
Great list! I have been a stay at home Mom for going on 4 years now. It is absolutely a sacrifice, both emotionally and financially to do so. I started looking into ways I could supplement our income, since my husband gets paid monthly. I do before/after school care most days, then during my free time I float between Amazon mturk and Swagbucks. Neither will make you rich quick.
Then once you’ve got your domain name and hosting sorted out, it’s time to pick a CMS, or Content Management System, that will let you update pages, build your blog and integrate with all the other services you need. It’s hard to go wrong with WordPress—the CMS powering close to a quarter of the internet. Keep in mind that eventually as you start growing traffic to your blog, you'll be wise to invest in a managed WordPress hosting plan from a company with great service like Kinsta, where all of the settings are custom-tailored and optimized to work particularly well with WordPress-powered websites.