There are quite a few people around, once you get into the (for want of a better word) "contact network". I played harp for years in the English folk scene, though now live in Ireland. Being able to busk & play by ear is more a matter of innate musical abilities, while playing the instrument in the most (again, for want of a better word) efficient manner is a matter of technique. (By technique I mean how you use your finger muscles to physically pull the strings. I do NOT mean issues of musical style, which is up to the individual musician.)

So get a teacher and learn the hand technique, and then play whatever music you want on your harp! Some good folks to get in touch with are Pilgrim Harps in South Godstone, Surrey, who know a lot of musicians and very much have a foot in the "folkie" camp as well as classical. You might try asking them (best person for that info is "John" who knows loads of people). They also have a list of teachers. Link is:

http://www.pilgrimharps.com/teachers.htm

Come back & let us know how you get on! So nice to see another harper here -

All the best, Bonnie