I'm with Zac here on just using a followspot. You could use a fogger or somethign of that nature to give it a cloudy look, but, in the dark, a followspot beam is going to show up well enough with the dust and dirt and everythign else that's normally in the air.
You can also buy a handle that fits on the
yoke of a
source four and allows you to move it something like a followspot, assuming hte fixture is up on a catwalk or some other accessible place. You could then use the
gobo.
Given that you're new at this, I wouldn't recommend jumping into an intel right off the bat. As Zac said, you're going to spend a significant amount of time programming one, even if you're well versed in programming the things.