I'm planning on starting color enlarging myself soon (I'm just waiting to receive a color print processing drum), so I can't yet offer any practical advice; however, to see what color enlargers look like, check these recent eBay auctions:
Originally Posted by Quinten
As Nick says, color enlargers have controls to adjust filtration. These are usually on the head (but not always -- check out the first link). Otherwise they're very much like B&W enlargers, although of course there's a lot of variability in details even within a type of enlarger. Most color enlargers use cyan, magenta, and yellow filtration to provide subtractive color adjustments. A few (again, check the first link) use separate red, green, and blue lights that provide additive color adjustments. In a public darkroom, I'd imagine you're almost certain to find the first type. That's also the type that's described in most books and Web pages on color printing.
You might want to ask whoever runs the darkroom what brand and model of color enlarger they've got. That way you can look it up on the Web. If you're lucky you'll find a manual -- or maybe you can peruse the manual at the darkroom without actually entering the color room. That should help minimize time wasted trying to figure out some silly detail.