ebook selling is always not easy and hence blog is the better option. Blogging can be done with the help of SEO techniques. It would succeed if done with precision.
i have to agree. updated blogs that are ranking high you can monitize in any number of ways. i have an ebook that i own rights to that i've been trying to sell for a year. when i first launched it it got some sales, but eventually it slowed down. it's even ranked pretty high too. go with the blogs.