Are you sure that avrdude (the program the Arduino IDE uses to upload to the Arduino) doesn't know how to find the USBasp device? It worked for me on a Macintosh and I didn't have to load any drivers.
Are you sure that avrdude (the program the Arduino IDE uses to upload to the Arduino) doesn't know how to find the USBasp device? It worked for me on a Macintosh and I didn't have to load any drivers.