Does anyone know where I can find a definitive list of switches that work with DSC? I would be particularly interested in any SOHO / Desktop switches that work with DSC.
…switches? I’m not sure what you mean.
I had heard that certain Microsoft branded / approved networking devices worked with DSC 
This Slashdot article hints at it:
With some googling I came across and OMI interface for Arista equipment:
I was just interested in purchasing a desktop switch so that I could try out configuring it without breaking the bank / production
Ah. So, you’re only going to find OMI in a managed switch, not a cheaper unmanaged desktop device. And I’m not aware of any master compatibility list; in theory, any switch supporting OMI should work, although you may have to write custom resources if the vendor hasn’t done so.