There are some amazing MAME arcade cabinets available to order these days. I've still not begun to remake mine, but I also had the idea to use an LCD screen to replace the very large and heavy 21" CRT I had in my old cabinet. Some of these new LCD based cabinets will give me a load of ideas on how to build my new one.

I wouldn't personally buy a pre-made cabinet. I would much rather build one from scratch, or customise a vintage real one.