I installed Audacity 2.0.3 from the CD that accompanied a new USB cassette player on my Windows 7 laptop.
The instructions say to set the recording device to be “USB PnP Audio Device”,
but the dropdown menu for the Recording Device field doesn’t include that
option. It only has the following two options:
Microsoft Sound Mapper - Input
Internal Microphone Array (IDT
If Windows “sees it”, Audacity can usually see it. Make sure to plug-in the USB before starting Audacity. It may not say exactly that, but it should say “USB… something”.
What version of Windows are you running? You should be able to right-click the Windows speaker/volume icon to open the sound settings/devices. If you find the USB device make sure it’s enabled, and there should be an option to [u]Listen To This Device[/u]. (You don’t need to enable that for Audacity but it’s a way to test the device without running Audacity or any other application.
If it’s not working, do you have another USB cable to try?
Those things are usually “cheap” and a lot of people have trouble with them. But, they do use the Microsoft-supplied drivers so it should be “plug-and-play” if it’s going to work.