There is also a mid level fireworks quest. I have a 27 monk and 34 rogue. They both got a fireworks quest that they need to get 4 Akanon skylighters from Castle Mistmoore, 4 Steamfont Geysers from Lower GUk and 4 Big 'Sploders from Solusek's Eye.
I'm doing that mid-level quest now with my 28 bard, but so far I haven't found any of the fireworks in Castle Mistmoore. I've been killing everything in sight. Do you know who or what drops them?