Not every church is blessed to have a large group of instrumentalists, but many churches have a handful of musicians who grew up playing in school band or orchestra who would like to serve with their talents.
These players could easily be plugged into ministry doing solos, duets, and various types of ensembles, not only in the worship service, but for various other functions as well. And for those who happen to have a larger group, it's still nice sometimes to break out into smaller units as the opportunity arises.
To help in finding music for such needs, let me call your attention to several sections of our website: First, there is Music for Solo Instrument; also Instrumental Duets. Music for Instrumental Ensemble features many types of instrumental groupings – brass, strings, woodwinds, etc. If you're looking for a choral number which features instrumentalists, be sure to check out Orchestrations to Choral Works and scroll down to access a PDF listing of choral arrangements, some fully orchestrated, but many scored for smaller ensembles. I hope you take a few minutes to check out these links.
Finally, let me direct your attention to an article I wrote for Creator magazine a number of years ago titled "Instrumental Music Ministry in the Smaller Church."
This may be found at:
(scroll down the page to find my article ... note that there is a nominal fee to access this).
As always, I'm available to assist you in any way with ideas for music and ministry. Write me at david@davidwinkler.com.