Serenade op 72 for Flute or Violin and Guitar by Joseph Kuffner (31 March 1776  - 9 September 1856).
(Three movements: Andante, Minuet allegretto, Rondo moderato.)

With downloadable mp3's for audio help (with both the Flute and guitar and one with guitar only for practicing the Flute).

Pages: 26 pages (7 pages Flute part, 7 pages guitar part, 12 page Flute and guitar), 11' min.

Mauro Giuseppe Sergio Pantaleo Giuliani (27 July 1781 8 May 1829) was an Italian guitarist, cellist, singer, and composer. He was a leading guitar virtuoso of the early 19th century.
This is the eighth of the set of 16 easy and pleasant duets for flute and guitar composed by Mauro Giulani at 1810.
For Flute and guitar duet.
With downloadable mp3's for audio help (with both the Flute and guitar and one with guitar only for practicing the Flute).  With guitar tablature.
Pages: Four pages (1 page both Flute and guitar, 1 page Flute part, 1 page guitar part, 1 page guitar with guitar tablature part), 1:15' min.

Ode to Whiskey by Turlough O Carolan (1670 – 25 March 1738) the great Celtic harper, composer and singer.

For Flute and Guitar duet. Early intermediate.

Guitar with standard notation and tablature and with finger position suggestions.

With downloadable mp3 just for audio help or practice.

Pages : Four (4) pages (2 pages score with both flute and guitar, 1 page flute part, 1 pages guitar with tab part).

Danny Boy is a famous ballad set to an ancient Irish melody with lyrics by English songwriter Frederic Weatherly.
For Flute and guitar duet.
Early intermediate.
With downloadable mp3's for audio help (one with both the Flute and guitar and one with guitar only).
With guitar tablature. With melody line. With lyrics.
Pages: four pages (score and Flute part)

Flow, my tears is a lute song by John Dowland (15631626). Originally composed as an instrumental under the name "Lachrimae pavane" in 1596, it is Dowland's most famous ayre, and became his signature song.
For duet  Flute and guitar. 
Intermediate.
With guitar tablature. With lyrics. With melody line. 
With downloadable mp3's for audio help (one with both flute and guitar, one with guitar only).

Pages: 4 pages (3 pages score, 1 page Flute part), 3:20 min.