Thanko USB to XLR Cord
Even though there are plenty of USB microphones out there, you may be quite particular to one specific or favorite microphone. To help bridge that gap comes the Thanko USB to XLR converter cord.
Simple as that, the cord is Windows and Mac friendly, 5 meters long, and requires no additional software and should be mostly plug and play. $55 may seem like a lot of cash to drop, but if it is essential to your situation, you may not have a lot of other choices.