The previous suggestions are all good ones, but if you want to consider a "DIY" approach, you could make your own isolation platform. Sorbothane works well for vibration isolation, but the prices for audiophile versions of this material are absurd. Here are 2 links to sorbothane items that work well and are very reasonably priced.
Links:
1. Edmunds Scientifics - sorbothane sheet: http://scientificsonline.com/product.asp?pn=3037000&cmss=sorbothane
2. Edmund Optics - sorbothane mounts: http://www.edmundoptics.com/onlinecatalog/displayproduct.cfm?productID=1618&search=1
