The first thing you need to do is to tell a harp-owner that you are interested in taking up harp and to ask if you may try playing their harp. You may be like me and find that you hate the feel and that you see two strings where one ought to be!Also, see if the American Harp Society has a chapter in your city. Go to the meetings and talk to the members. Can you rent a harp and take some lessons?
Do not teach yourself by buying a Sylvia Woods book. Her harp technique has a dubious reputation.
Then, if you think the harp is for you, at least buy one with levers. I have played with a lot of harpers, and a harp which must be retuned simply to go from C to G is not worth it. Remember, if the harp is for you, then you might own this thing all the rest of your life.