hmm Cootehill...
being from the other end of the country, I suppose I'm missing loads, but here's a few.
There's definately a (concert) band in Kingscourt, Cavan, but their website is down at the moment, and I can't locate contact details for you
http://www.stmarysbrassandreedband.com/
Kingscourt is about 15 miles from Cootehill.
Other options include a band in Monaghan Town (about 15 miles in the other direction) and a youth band in Belturbet (about 10 miles away) but I think this is an accordian band. Hard to find out info.
If you're willing to travel, There are a few bands on the go in Co. Meath. Drogheda, Lourdes, Kells, Navan (x2) are all friendly, and there's Dundalk in Co. Louth. Alternatively, I'm sure you'd be tripping over bands across the border in the North.
Hope this helps.
P.S. If you're ever in the south, give us a shout..
Kepps