You can find both SoundSlice implementation and tons of blues fingerpicking courses (beginner through advanced) at TrueFire's guitar site. GT is home base for me but I also use TrueFire because they have a staggering collection of full courses in a wide range of genres, and for every skill level. Song collection is pretty meager compared to here, though. Anyways, they offer membership sales almost every day. Their recent Cinco de Mayo sale offered a one-year full access membership (usually $255) for just $55.

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