Hebe Online, catalogue by categories/instruments

Guitar solo
Two guitars
Three guitars
Guitar and one other instrument (violin, flute, violoncello, etc)
Guitar and two or more other instruments (violin, flute, violoncello, etc)
Voice and piano
Voice and guitar
Voice and piano or guitar
Piano solo
Book
Catalogue by authors / composers

Hebe Home Page.

You can also consult the catalogues on the Tecla website of printed music.