Click here to download:

BlackBerry_3G_CID1 (7 KB)

Apparently, this thing works incredible easy. Easy to setup, easy to use.

I would suggest to read this thread The How To: To Mac Tethering: Your Problems Solved (http://forums.crackberry.com/f62/how-mac-tethering-your-problems-solved-260401/) on Crackberry, or may own experience is right here:

So, I've been using:

Blackberry Bold 9000 AT&T (4.6.0.297 on 4.0.0.247 platform)
Snow Leopard (10.6.1) on Macbook Air

Steps are the following:

 1. on Mac: turn on Bluetooth
 2. on BB: Setup -> Setup Bluetooth -> ...
 3. on BB: set device name for pairing, click OK, then Listen, it will start waiting for connection
 4. on Mac: System Preferences -> Bluetooth -> Setup new device -> ...
 5. on Mac: choose your mobile phone name, click Continue
 6. on BB: enter passkey which will be on your Mac screen, click Enter
 7. on BB: choose Yes, and check off Do not ask again
 8. on Mac: Bluetooth Mobile Phone setup screen will ask for data
 9. on Mac: Vendor = Other
10. on Mac: Model = Blackberry 3G CID1
11. on Mac: Check off Enable error correction and compression in modem
12. on Mac: Dial mode = Wait for dial tone before dialing
13. on Mac: Dialing = Tone
14. on Mac: Sound = On
15. on Mac: Username = wap@cingulargprs.com
16. on Mac: Password = CINGULAR1
17. on Mac: APN = wap.cingular
18. on Mac: Click Continue
19. Enjoy tethering - Connect Bluetooth DUN and that's it.

It's not 1-2-3, but it's fairly easy.

Before starting - you need to unzip this archive into /Libary/Modem Scripts/ or you will not have proper modem script for the Blackberry Bold.