The three best and most popular series for brass congregational accompaniment of contemporary worship songs are:
Scripture Based Songs
The Hallelujah Choruses are designed to work with any combination of instruments, whether it is brass, woodwind, or stringed instruments. You can also combine the contemporary worship band with the brass band on these arrangements, as keyboard, guitar and bass charts are also provided. The series works with a small or large ensemble of players, so it is the most versatile of the three mentioned above. It is published by The Salvation Army Territorial Headquarters USA Central Division, out of Chicago, and is available for purchase from your local SP&S or Trade stores. You can purchase for a whole brass band, or just the worship team. SATB parts are also available, if you would like to use any of the pieces with your songster brigade. Finally, at a very low cost, you can choose to purchase lead sheets only. A new volume (ten pieces per volume) is published every couple of years. Click on the title link above for an index of all songs available.
Scripture Based Songs are brass accompaniment only (does not gel with contemporary worship team members), but the pieces are very well arranged. It is published out of the UK, and a new volume of songs appears every couple of years (12 songs per volume). Again, click on the title link above to see an index of pieces, and contact your local SP&S/Trade Dept to order.
Finally, Magnify is also published out of the UK and is a volume of 75 popular worship songs. There are a couple of repiano brass parts that need to be purchased along with the normal parts in order to make the brass accompaniments work. Although there is a coinciding piano songbook, the songbook does not mesh with the brass arrangements (even the keys aren't always the same), so the choice of accompaniment is one or the other. Still, it is a practical series to own.
Finally, if you are really needing an accompaniment that doesn't exist in any of the above series, you can check out praisecharts.com
. They have full orchestrations of all the popular contemporary worship pieces, although you will be paying for woodwind and string parts along with the brass.