(2016-08-16 at 09:30)MacInTouch Reader 683 wrote: Can anyone suggest how to get one of these USB/WiFi adapters working on my MacBook Pro? Is there a source for compatible drivers?

Macintosh compatibility with USB WiFi adapters is not as popular as it is for other computer platforms, but there seems to be only a couple of companies that write WiFi drivers, so you might be able to find a WiFi driver that will work with your MacBook Pro. Do a search using the brand of WiFi adapter and then continue to search for 'drivers for brand 'x', model 'x' USB WiFi adapter'.
Mac WiFi drivers are offered for the specific operating system, rather than for a particular computer, so, for example, you would need one set of WiFi drivers for a Mac running 10.9 and another set of Mac WiFi drivers if you are running 10.6.
We've had good luck with the inexpensive 'Rosewill' brand WiFi adapters sold by NewEgg that offer WiFi drivers for Macs - ours have worked pretty well with older Mac computers than what you are using, including a G4 Powerbook and an even older G3 Pismo. Check to ensure they have drivers for your operating system.
(If you can get away with it, you might want to consider using an Ethernet cable with your MacBook Pro to get better bandwidth and greater stability, instead of using WiFi.)
Note that the USB WiFi adapters we've used with our Macs get quite hot, so it might be advisable to connect them using a 'USB extension' cable. Some USB WiFi adapters are sold with a USB extension cable connected to a small vertical USB 'stand' to plug in the WiFi adapter as a free-standing unit away from the computer. For a laptop, using an extension USB cable might be a nuisance, but monitor the heat that the USB WiFi adapter puts out, and if it is excessive, think about adding a USB 'extension' cable to connect your USB WiFi adapter.