Congratulations! May this be a long term relationship!
I play both fretted dulcimer and celtic harp. I strongly suggest finding a good teacher. (A celtic harp teacher as opposed to a classical harp teacher. Or one who does both.) Books can only take you so far....often into a land of bad habits and frustration. Books can't help you with your own personal hand position and sound. And books can't marvel at you when you learn something new on the harp, but a teacher can. (Your friends and family won't get so excited, believe me....)
One of my biggest thrills is having learned how to play harp by ear. With the right teacher, in less that a year, I was able to play over 30 pieces with a viola player at a wedding.
Well, that's my wee opinion. No, it's my strong opinion. There are books out there. But I say, get yourself a good teacher.
(my harp and my dulcimer are both made from black walnut)