On the AVRDUDE web page, http://www.ladyada.net/make/usbtinyisp/avrdude.html
("For Windows" section) it says "If you're using WinAVR, replace libusb0.dll, avrdude.exe and avrdude.conf (make backups though!) in C:\WinAVR\bin"
I'm probably missing something obvious, but replace them with what?
Thanks

