Tablature, which might be worth a try. It takes a while to get the hang of it, but it is useful. It might be worth seeing if the library will get you something by, say Stephan Grossman: there is a book of 'Celtic' guitar by Grossman and John Renbourne which might appeal. Also one by Duck Baker of Irish jigs for fingerpicking guitar style. Just a thought. If got via the library you don't have to lay out lots of money to see if it suits.