I need to unlock a 3GS

[KoukiFC3S]

I am not sure what firmware this 3GS is running, but it is currently showing the iTunes logo when plugged in my PC.

It's been like that for about 2 months, so I don't think the phone has 4.1 or 4.2.1.

How should I go and put 4.0 on it and unlock it? Thanks!

 

[Applejuiced]

Plug it in to Tinyumbrella to find out what firmware its on and to see if it has any SHSH's on file.

 

[labman]

also at your baseband from there search for jailbreaks and unlocks Iclarified is up to date and has all the tutorials.