Some general ideas:
Timbernation is one of the better vendors I see around, Ikea for really cheap if you can find what you want, but frankly most audiophile racks are either crap or grossely overpriced.
Consider hiring a trim carpenter (with the economy/housing market) builders are dying for work. He could match your furniture, build to your exact wants, even do a built-in.
You didn't ask about design, but in 40 years at this, I've never heard a rack contribute, except negatively on soft wooden floors (consider wall mounts, especial if you have vinyl).
And above all else, find something you can slide in and out to make equipment changes easier.
