The search function is your friend. This has been covered many many many many many many...many times. It does seem though that you have actually looked at some of the posts so I will copy this here.
This is from a post I wrote a while back:
To use bluetooth, make your phone discoverable and click on the bluetooth symbol on the top of your Mac;s screen and choose "Setup bluetooth device and follow the directions.
Go to System preferences and choose Network. Click the + to add a service if Bluetooth DUN is not there. Choose Bluetooth DUN from the drop down menu for the interface.
These are the settings I use.
Telephone number: leave blank
Account Name: WAP@CINGULARGPRS.COM
Click on Advanced >Modem
APN: wap.cingular CID: 1 Vendor: Research in Motion Model: Blackberry IP Modem GSM
Here is a link to a thread about this in the Mac area on Crackberry: Blackberry Bold: My successful AT&T tether settings. OSX 10.5.6 and BB OS .167
The settings shown in that thread are the same with the exception of the phone number. They had something in the phone number field but that didn't work for me. Leaving it blank did.
I hope this helps. It is actually quite easy.
Here is the link to that thread, http://forums.crackberry.com/f209/to...anager-514417/