I would recommend Blackra1n. :)
iPhone/iPod Touch/iPad iPhone: 1G, 2G, 3G, 3GS, 4 iPod Touch: 1G, 2G, 3G iPad
Yes, use PDAnet to connect it. To get PDAnet you will have to jailbreak your iphone.
no, you dont. you can jailbreak your iphone and run it on tmobile's network, if you have a tmobile sim card. but on tmobile, you cant have 3g speeds, only 2g.
redsnow which you will need to jailbreak its the easiest way to do it and its free
Go to blackra1n.com
No. Jailbreak is out yet for 2G. Chronic Dev is workin on it. dec13/08
Ziphone, google it :)
Actually, the iPhone 3g and iPod touch 2g can be jailbroken with a program called redsn0w. Just google it and click on redsn0w.com or something like that and download. Its not that hard
Absinth
The iPhone 2G is much slower than the iPhone 3G.
The app installer on the ipod touch or iphone requires a jailbreak. You can do a quick search on google on "install quickpwn" and that will help you jailbreak your iphone 3g or the ipod touch 1st generation. NOTE: THE JAILBREAK FOR THE IPOD TOUCH 2G IS NOT AVAILABLE YET! If you have an ipod touch 1g or iphone 3g, type in on google "how to use quickpwn" and you should learn how to jailbrek your device.
Yes