A few weeks ago, a local ham of my acquaintance told me about the Hermes Lite SDR radio. It's available from makefabs.com fully assembled for about $300. I happened to have the money for it, so I said "why not?" and ordered it.
It took a while (makerfabs is in Taiwan, and they make them in batches so you can wait quite a while if your timing is as bad as mine) but the radio finally arrived. I've been using quisk to receive signals with it and that seems to work. Quisk is much easier to work with when you're using it for something it actually supports.
I'm also looking at something called SparkSDR, but it doesn't work for me. I'm getting help with it, and I'm sure we'll figure out what's wrong with my system soon enough.