Oh yay, something I can help with!
For the Atheros AR5B125, I just read an article on osx86 about you not needing one. http://www.osx86.net/topic/16740-ar5b125-atheros-kext/
Maybe at this point, you're thinking "No because it's not working..." That is at first what I thought. What you do to activate it is as follows:
1. Obtain your Device ID and your Vendor ID. There is an application for Mac, Windows, and Linux that can list these. Here is the link:
http://www.osx86.net/file/2243-system-info/ The MacOSX version is the SystemInfo.zip.
2. Now we are going to find where the .kext, or Kernel Extension, for your device is. Is it located in /System/Library/Extensions or Extra/Extensions?
3. Once you find it, use one of these commands in the Terminal depending on where the .kext is located.
sudo nano /System/Library/Extensions/[yourwifidriver].kext/Contents/Info.plist
sudo nano /Extra/Extensions/[yourwifidriver].kext/Contents/Info.plist
4. Once in, scroll down and try to locate <key>IOPCIPrimaryMatch</key> or <key>IOPCINameMatch</key>. If you find <key>IOPCIClassMatch</key> instead, change IOPCIClassMatch to IOPCIPrimaryMatch.
Below the key you should see a string of numbers either preceded by 0x or pci. Delete all the strings there, and enter in your Device ID in this order:
0x[deviceID][vendorID]. Remember to omit the period.
If you had <key>IOPCINameMatch</key>, then enter your Device ID in this order:
To show you an example, I will use 96ef as my Device ID, and 3602 as my Vendor ID.
If you had <key>IOPCIPrimaryMatch</key>, then 0x96ef3602 is what you would enter. If you had <key>IOPCINameMatch</key>, the you would enter:
Once done, press Control+O and Control+X. Now reboot and at the boot prompt type -f.
I hope this helps you!