Send me a PM and I'll hook you up, MT56. :)

89 SAB Motet titles currently at CPDL (using Mulit-Category Search):

A Prece dos Filhos do Fogo (Fábio Soldá)
Agatha laetissime (Pietro Vinci)
Alles was ihr tut (Constantin Christian Dedekind)
Amen. Lob und Ehre und Weisheit und Dank (Georg Philipp Telemann)
Angel dal ciel disceso (Giovanni Giovenale Ancina)
Ave Maria (Noel Jones)
Ave Maria 3-part (Anonymous)
Ave Maria a 3 (Charles H. Giffen)
Ave Maria a 3 (Francesco Lorenzo Luciani)
Ave Maria a 3 (Ramiro Real)
Ave Maria I (Adrian Cuello)
Ave verum corpus, KV 618 (Wolfgang Amadeus Mozart)
Ave verum III (Charles Gounod)
Barechu (Salamone Rossi)
Beata viscera Mariae (Mattia Culmone)
Benedictus qui venit (Alonso Lobo)
Bonum est, Op. 296, No. 4 (Robert Führer)
Bonus Est Dominus (Giovanni Pierluigi da Palestrina)
Cantate Domino (Johann Crüger)
Cantate Domino, Op. 296, No. 6 (Robert Führer)
Christe der du bist Tag und Licht IV (Michael Praetorius)
Christus gibt durch den Tod das leben (Samuel Jacobi)
Da pacem Domine, Op. 296, No. 1 (Robert Führer)
Decantabat populus (Giovanni Matteo Asola)
Deus meus a 3 (Alessandro Grandi)
Deutsche Vesper (Franz Bühler)
Dies ist der Tag (Georg Philipp Telemann)
Ecce Maria genuit (Rudolph di Lasso)
Erhalt uns Herr bei deinem Wort a 3 (Michael Praetorius)
Exaudi Deus (Giovanni Paolo Cima)
Gelobet sei, der da kommt (Constantin Christian Dedekind)
Gelobet seist du, Jesu Christ (Melchior Schärer)
2 Gradualia (Anton Diabelli)
6 Gradualia vel Offertoria (Karl Kempter)
Gut ist es (Robert Führer)
Haec dies a 3 (William Byrd)
Halt im Gedächtnis (Georg Philipp Telemann)
Herr unser Herrscher (Johann Staden)
Herr, mein Gott bist du (Robert Führer)
Hosanna (Mark Chapman)
Hosianna, dem Sohne David (Georg Philipp Telemann)
In te Domine speravi (Dietrich Buxtehude)
In te Domine speravi, Op. 296, No. 2 (Robert Führer)
Jesu mi dulcissime (Mariano Garau)
Jesu Rex admirabilis (Giovanni Pierluigi da Palestrina)
Komm, heilig guter Geist (Constantin Christian Dedekind)
Lauda anima, Op. 296, No. 5 (Robert Führer)
Magnificat (Mariano Garau)
4 Marianische Antiphonen (Karl Kempter)
4 Marienantiphonen mit Orgel (L. B. Est)
Miserere mei, Deus (Pulvis Filius)
Mit Fried und Freud fahr ich dahin (Adam Gumpelzhaimer)
7 Motetten (Charles Gounod)
Non nobis Domine, Op. 296, No. 3 (Robert Führer)
Non turbetur (Giovanni Paolo Cima)
Not For All Desire (Gabrael StClair)
Nun komm der Heiden Heiland (a 3) (Michael Praetorius)
Nunc dimittis (Samuel Jacobi)
O bone Jesu (Michelangelo Grancini)
O Heiland, reiß die Himmel auf (Burkhart M. Schürmann)
O magnum mysterium (Mariano Garau)
O sacrum convivium (Gregor Aichinger)
O sacrum convivium (Roberto Remondi)
4 Offertorien (L. B. Est)
Pater Noster (Adrian Cuello)
Plange quasi virgo (Mariano Garau)
Puer natus est (Cristóbal de Morales)
Quam dilecta (André Campra)
Regina Coeli (João Baptista Lehman)
Rorate coeli (C. Titsek)
Schaffe in mir Gott (Christian Prein)
Sechs kurze und leichte Offertorien, Op. 296 (Robert Führer)
Shir Hama'alot (Ps. 128) (Salamone Rossi)
Souterliedekens - Psalm 131 (Jacobus Clemens non Papa)
Souterliedekens - Psalm 140 (Jacobus Clemens non Papa)
Souterliedekens - Psalm 4 (Jacobus Clemens non Papa)
Souterliedekens - Psalm 5 (Jacobus Clemens non Papa)
Stabat Mater (Adrian Cuello)
Subvenite Sancti (Nusch)
Tota pulchra (Mariano Garau)
Triumph, Triumph, Victoria (Andreas Hammerschmidt)
Ubi est Abel frater tuus? (Gregor Aichinger)
Vere languores (Antonio Lotti)
Verhoort Heer myn gheclach (Jacobus Clemens non Papa)
Verleih uns Frieden (Johann Kugelmann)
Vias tuas (Anton Diabelli)
Viel schöner Künst und Gaben (Sethus Calvisius)
Wie schön singt uns der Engel Schar (Cornelius Freundt)
Das Wort ward Fleisch (Constantin Christian Dedekind)

52 SAT Motet titles currently at CPDL (using Mulit-Category Search):

Alleluia. Vespere autem Sabbathi (William Byrd)
Aller Augen warten auf Dich, Herre (Christoph Dalitz)
Ave Maria (Claudio Monteverdi)
Ave verum a 3 (Josquin des Prez)
Benedictus qui venit (Alonso Lobo)
Benedictus qui venit (José de Torres)
Benedictus qui venit (Philippe Rogier)
Blessed art thou that fearest God (John Mundy)
Decantabat populus (Giovanni Matteo Asola)
Domine exaudi vocem (David Thoman)
Ecclesiae militantis (Guillaume Dufay)
Elevación o ascención, gradación y descenso (Francisco Valls)
Faith Is (Gabrael StClair)
Gustate et videte (Giovanni Matteo Asola)
Haec dies a 3 (William Byrd)
Hic est Beatissimus Evangelista (Giovanni Maria Nanino)
Homo quidam (Anonymous)
In die tribulationis (Damião de Góis)
Jesu, Salvator mundi (Menegali)
Lapidabant Stephanum (Giovanni Maria Nanino)
Lauda Sion Salvatorem (Claudio Monteverdi)
Mater Dei - Mater virgo - Eius (Anonymous)
Mit Fried und Freud fahr ich dahin (Adam Gumpelzhaimer)
Nisi Dominus a 3 (Tomás Luis de Victoria)
O altitudo divitiarum (Giovanni Paolo Cima)
O altitudo divitiarum (Sigismondo d'India)
O beata beatorum (Johannes Roullet)
O bone Jesu (Claudio Monteverdi)
O come, let us lift up our voice (John Mundy)
O Jesu Christ, mein Herr und Gott (Adam Gumpelzhaimer)
O Jesu, mi dulcissime (Felice Anerio)
O Lord, turn not away thy face (John Mundy)
O sacramentum pietatis (Francisco Valls)
Panis angelicus a 4 (Claudio Casciolini)
Puer natus est (Cristóbal de Morales)
Quam pulchra es (Claudio Monteverdi)
Regina coeli laetare (William Byrd)
Salve mater misericordie (G. Dupont)
Sancta Mater, istud agas (Fabio Fresi)
Sol occasum nesciens (Heinrich Isaac)
Souterliedekens - Psalm 60 (Jacobus Clemens non Papa)
Speciosa facta es (John Dunstable)
Tantum ergo (Before the Holy Mystery) (Douglas Brooks-Davies)
Tantum ergo (Claudio Casciolini)
Thus art thou blest that fearest God (John Mundy)
Tota pulchra es a 3 (John Forest)
Ubi caritas et amor (Douglas Brooks-Davies)
Veni Creator Spiritus (Gilles Binchois)
Verbum caro (Tomás Luis de Victoria)
Virgo rosa (Gilles Binchois)
Vox in Actus (Denis Nogueira)
Ye people all in one accord (John Mundy)

Can you please post it?

I like Baini's Panis Angelicus. We're doing that one in choir right now. Few rests, and all three voices sing at the same time throughout the song, so nobody has to sit and count while others sing, and then miss the entrance. It's also quite beautiful.

Of the motets listed by Charles, my favorites are:

Jesu Rex admirabilis - Giovanni Pierluigi da Palestrina
Ave Verum Corpus - Josquin des Prez

A motet not on Charles's list but definitely worth doing (scored for SST but it can be taken down a minor third):
Tua Iesu Dilectio - Palestrina

A nice Ave Maria by Ravenello, edited by our own Jeff Ostrowski

You may also want to look at the Chester Book of Motets, vol. 7: Motets for Three Voices for some other ideas.

@Francis, here is the score from CPDL, where I found it.

http://www1.cpdl.org/wiki/index.php/Panis_angelicus_(Giuseppe_Baini)