Hi Chris,
For what you're looking for you'd probably more interested in a product like the Z-Wave PC SDK. Currently, it's available for .NET on Windows platforms, although we have a Mono-compatible implementation in the works (for Mac OS X, Linux, etc.)
The other solution for you is to pick up the Vizia RF Foyer or Leviton's Vizia RF serial adapter, which will let you talk some or all Z-Wave via an Ethernet/RS232 connection on your Linux machine.
Chris