So you want to unlock your iPhone 3G?
Well, you need to start off with a Jailbroken iPhone 3G. You can Jailbreak your iPhone 3G (On Firmware 2.2) buy referring to this tutorial. (Click for PC Tutorial
and Click for MAC Tutorial
After that, follow the below video.
If your too lazy to let the video load and get a good look at how to do it, you can just follow the below steps.
1. Restore to Firmware 2.2 (Download here)
2. Download QuickPwn (Download here)
3. Jailbreak your phone (Follow this tutorial MAC
4. Go to Cydia, Add the Repository ("http://apt9.yellowsn0w.com/")
You can do this by going to Manage > Sources > Edit > Add.
You need either Wi-Fi/EDGE for the step onwards, ofcourse.
5. Search for "yellowsn0w" in the Search tab in Cydia. Download and Install.
6. Search for "BossPrefs". Download and Install.
7. Close Cydia. Open BossPrefs, restart your iPhone using the BossPrefs Restart option. (BossPrefs > Power > Reboot)
8. Wait for your phone to boot up, again open up Cydia, and reboot using BossPrefs again.
9. Wait for your phone to boot up, you should see Signal appearing. Test calls/sms/data, etc.
10. If for whatever reason, you dont get signal. Remove your SIM, put in back in.
11. Wait 1.5 minutes, Enable Airplane Mode, Wait 10 Seconds, Disable Airplane Mode.
12. You should see Signal appearing. If not, your outta luck!
(Try one more BossPrefs Reboot)
If you have any questions, post below