The Orthodox call Peter and Paul "The Holy Glorious and All-Praised Leaders of the Apostles, Peter and Paul"; here are Troparions and Kontakions for their joint feast:
The Metropolitan Cantor Institute - a fantastic resource! - offers some other chants as well; here is the complete listing for this feast. The links go to mp3 files.
Here's a PDF of "The Akathist Hymn to the Holy Apostles", from the website of the Antiochian Orthodox Church.
Here's a video of a 1988 "Patronal Feast" of Ss. Peter and Paul:
Troparion
First-enthroned of the apostles, / teachers of the universe: / Entreat the Master of all / to grant peace to the world, / and to our souls great mercy!
This video is in Georgian, I believe, and says it's "Troparion to the Saints, Tone 4," and uses the same words as above:
This is an mp3 of the same Troparion, from the Metropolitan Cantor Institute of the Byzantine Catholic Archeparchy of Pittsburgh.
Kontakion
O Lord, You have taken up to eternal rest / and to the enjoyment of Your blessings / the two divinely-inspired preachers, the leaders of the Apostles, / for You have accepted their labors and deaths as a sweet-smelling sacrifice, / for You alone know what lies in the hearts of men.
Here's an mp3 of this Kontakion, again from the Metropolitan Cantor Institute of the Byzantine Catholic Archeparchy of Pittsburgh. The words are slightly different here.
Kontakion
Today Christ the Rock glorifies with highest honor / The rock of Faith and leader of the Apostles, / Together with Paul and the company of the twelve, / Whose memory we celebrate with eagerness of faith, / Giving glory to the one who gave glory to them!
I don't have audio for this one; too bad, because it's a beautiful text!
The Metropolitan Cantor Institute - a fantastic resource! - offers some other chants as well; here is the complete listing for this feast. The links go to mp3 files.
The Holy Apostles Peter and Paul (June 29)
- Troparion - Kontakion - Magnification - Irmos (simple setting) - Irmos - Communion Hymn
Here's a PDF of "The Akathist Hymn to the Holy Apostles", from the website of the Antiochian Orthodox Church.
Here's a video of a 1988 "Patronal Feast" of Ss. Peter and Paul: