This was probably covered in "old Tubenet" but I thought I'd give it a mention in case it was forgotten or not known about. While on the way to the ISB (bassist's) convention in Kalamazoo I went up to Ann Arbor to visit relatives, and they mentioned the Tuba Museum in the Lansing area near where their daughter goes to college at Michigan State. The town is Okemos, south of E. Lansing, which is off exit 110 on I-96, go straight north and you'll run right into it.
I'd heard of it before, probably from this forum, and was adventurous enough to take the detour. Glad I checked it out. It's just a little hole in the wall place, food seems passable, but has a nice varied collection of older tubas, sousas, helicons, euphs, and other such beasts. Got a bunch of pics, which are about the same as their site:
http://www.travelerstuba.com/travelersclub_001.htm
They also have coffee mugs, T shirts, postcards, etc. It's worth the visit if you're in the area. Interesting music store behind it too.
Ike