I play for a church that is very traditional, just recently they have started to be more open to contemporary music.
The best way to play traditional music?
1. Start with those old hymnals. You will find a lot of great stuff in there. Playing out of that old hymnal will force you to play is keys you don't usually play in and brush up on your music-reading skills.
2. Now put in your major sevenths, runs and fills.
3. Listen to some Shirley Ceasar, Dorothy Norwood, Richard Smallwood, Richard "Mr Clean" White. There are some CD's out there that have collection of Old-Time Gospel favorites, and they really aren't that expensive.
4. Learn some songs from the days of the SuperChoir (late 1970's, early to mid 1980's). The "old" music from the New Jersey Mass Choir, Mississippi Mass, etc have some really good songs that are a good bridge between traditional and contemporary (actually, the SuperChoir
was the transition between traditional and modern).
5. Finally, can I issue an impassioned plea to please let's push our musicians to read music. Pretty please. An entire generation of musical ideas can be lost if we do not write them. Too many of our musician's can't read music, and it is costing us BIG time.
Just my 2 cents