My wife has been looking for a curio cabinet for several months on Craigslist. The style she wanted, and eventually found, was a curved-front type like this:
The curio cabinet that she bought is not an antique. Instead it is a 1970's vintage piece that looks like the antique version. We bought it from the estate of an elderly lady who had passed away. The curio cabinet was in excellent shape and not expensive, due to the later vintage.
The first thing we did was remove the shelves, and took them down to a glass shop. The glass shop used the shelves as templates to cut new glass shelves. While the shelves were out of the cabinet, I cleaned it. Afterwards I installed foam weather-stripping around the door opening to minimize dust buildup inside.
Next I purchased and installed some really nice LED under-cabinet lights from Home Despot. They throw a nice light that looks like it came from a halogen bulb. Picture below:
I installed the new glass shelves, and anchored the cabinet to the wall. The result is pretty nice.