I'd recommend shooting at the 18mm end and getting as close as possible.
I would also recommend shooting with the flash, but set it to -2 FEC [flash exposure compensation] so the flash exposure does not overtake the photo.
I'd also recommend hooting at ISO800- ISO 1600 to avoid camera shake.
Will you be able to invest in the Canon 50mm f/1.8 lens? It is small, cheap, and optically fast.
I would google search band shots or search around here to get some creative inspiration.
Nikon D700/D300|17-35 f/2.8, 24-70 f/2.8, Sigmalux, 80-200 f/2.8, 16 f/2.8 fisheye,
Lots of flashes and Honl gear.