Most pieces are in standard "open G" tuning (gDGBD), but there might be one or two in alternative tunings as well. The titles for open G tuned plectrum banjo works just as wellon a fivestring banjo btw.
Tenor banjo
Various tunings:
Standard tuning (CGDA): Choose "Tenor banjo" in the Instrument menu. Most of the Irish tenor banjo pieces also work in standard tuning, although they end up in a different key.
DADA tuning: Choose "Tenor banjo (DADA-tuned)."
CGCG tuning: The DADA titles works just as well in CGCG tuning. Use a capo in the 2nd fret if you need them to be in the "right" key.
Irish tuning (GDAE): Choose "Irish tenor banjo". The standard tuning titles can also be played in Irish tuning, but if you want them in the "right" key, you have to use a capo in the 7th fret.
AEAE tuning: The DADA tuned titles will work. Use a capo in the 5th fret to get the original key
GDGD tuning: Play the titles for DADA-tuning ,- with a capo in the 7th fret if you need them in the key they're notated in.
High C tuning (cGDA): Choose "Tenor banjo" and have a look. Some of the titles might work with a high octave fourth string.
High G tuning (gDAE): Most of the Irish tenor banjo titles should work, but you won't use the fourth string much.
Plectrum banjo tuning (CGBD): See plectrum banjo.
Open G tuning (DGBD): See plectrum banjo.
Chicago or "guitar" tuning (DGBE): See plectrum banjo.
Other tuning: Sorry, nothing here at the moment, but have a look in The Mandolin Archive.
Plectrum banjo
Some of the titles are for standard (CGDB) tuning others for open G (DGBD). For other tunings:
Irish tuning (GDAE): See tenor banjo.
Chicago or "guitar" tuning (DGBE): Choose "Plectrum banjo (Chicago-tuned)." Many of the guitar-banjo pieces works well on a fourstring instrument too. Just ignore the two lowest strings.
ADAD tuning: See tenor banjo.
GCGC tuning: See tenor banjo.
Guitar-banjo
Most of the titles are for standard tuning (EADGBE), but there might be one or two for other tunings as well. Some of the titles in The Guitar Archive should sound good on a guitar-banjo. The plectrum and tenor banjo pieces in the appropriate tunings work well on a guitar-banjo too. Just ignore the two lowest strings on your instrument.