Pick some simple songs that you know very well. Then figure them out for yourself. Oh susanna, you are my sunshine are some old examples, but any song you know and like. Start simple. Learn a song, then another, keep practicing each of them!

This site is incredible,

http://www.bluesharmonica.com/

It’s a monthly subscription but it gives you lessons and video tutorials and the tab notation to print out. I’m a professional musician already and learning harp on the side but I think it would be good for beginners also.