My bulb has burned out after years but I can't figure out how to take off the dome to replace it? Any ideas?

Push up on the globe and carefully turn it to the left. Should drop down.

How about a picture of the fan?
Since we are not Home Depot I don't think many of us are familiar with a harbor breeze 69 airspan.

Is this it?

Harbor Breeze 69 Airspan Ceiling Fan Free Manual | Photography (http://duoliphotography.com/duoli-photo/harbor-breeze-69-airspan-ceiling-fan-free-manual.html)

Looks like a simple retaining cap on the bottom of the globe.