Questions for iOS4

Jailbraking, how fun...

My iPhone 3G is currently un jailbroken and I would like to jailbreak it to iOS4 and have free tethering with my Unlimited Data plan because unlike the idiots with iPhones and no comprehension of Jailbreaking I did not change my plan and I will be keeping the grandfathered Unlimited Data plan.

Now what redsn0w program should I use for jailbreaking?

4.0 or 4.0.1? I do not know if the latter is available for iPhone 3G.

ATT never detected me tethering on my iPhone 3G when tether was 3GS only, why are people telling me it will be detected now.

What programs should, a guy with about level 4 on a scale from 1-10 jailbreaking program knowledge, get