Theo Ellsworth's stuff is located in the Eugene, OR Library. Might be around where you are as well. Capacity is a big book, like a 3-4 year collection or something like that.

Another resource you might consider checking out, if you're into upping your art skills, and hanging out with people who are also passionate about self-publishing children's books would be https://oatleyacademy.com/

Magic Box is digital painting lessons.
And Storyteller's Summit -- I think, is a storytelling 101 type course. They are both subscription based, and super affordable. You could pay for it each month with your HIVE / STEEM earnings, likely.

While you subscribe, you also get access to a community forum full of artists who are doing SFW children's book type projects, and there are a bunch of podcasts and such where they give insight into DIY Financials of self employed / self publishing artists / animators etc.

Really an excellent program.

I've gone through the Magic Box program once myself, and listened to the podcasts, and done some work in storyteller's summit.

As far as actual art skill development, I prefer Noah Bradley's Art Camp, but that's mostly because Noah's crowd is more alright with Nude Women, which happens to be what I paint a lot of.