The fan has a dome cover. There are three "tiers" - the lower dome, center fan blades, and top casing. When I try to turn the lower dome to remove it, the lower and top casing rotate and the dome does not drop out (as an earlier answer suggested it might). Is there something I am missing?

I broke my bulb on a hampton fan (unfortunately - I rested the unit on the bulb and it shattered). I purchased a replacement from King Of Fans (http://www.kingoffans.com). At the time (a few years ago) it was the only place I could find to help me.

Posting a pic of the light would help more than anything.

OK, I found it easliy enough.
http://static.howstuffworks.com/gif/productImages/0/9/66611110027009-large-King-Of-Fans-Hampton-Bay-54-Inch-Windward-II-55296.jpg

The glass should twist off in a CCW rotation. It will only take a fraction of a turn for it to come down.