Currently I have a
IPhone 3G
and Jailbroke it once before and used Ultrasn0w to Unlock the SIM
I want to update my IPhone But How?


I want to update my IPhone But How?
There is no Pwnagetool for Windows....so i'm screwed
No, you aren't. The Dev-Team is working on a multi-platform (Mac/Win/Lin) version of PwnageTool. You can also obtain a custom IPSW file from the internet. Please don't ask here; we are not allowed to distribute copyrighted materials.
Finally, you could always update to 3.1.2 and then jailbreak with blackra1n and unlock with blacksn0w. Be aware that updating to 3.1.2 stock will upgrade your baseband and you will no longer be able to use ultrasn0w. Also be aware that a minority of blacksn0w users have experienced intermittent WiFi connectivity problems with blacksn0w.
I can't use Blackra1n because i used Ultrasn0w to Unlock my SIM in the first place *sigh* I guess i'm stuck at 3.0 for the mean while
Pwnage Tool supports it.
Create the custom IPSW and option restore in iTunes
can someone pleeeeze explain in detain how to create a custom .ispw file with the pwanage tool, cause i have no idea how to do it.