I have been reading and reading.........but am unsure what to do!

Do I Jailbreak and unlock my iphone 3G or use a Magicsim turbosim duelsim........whatever!

Can anybody just tell me the best way????
Which also works for everything!

Also does anybody know this site........http://www.magicsim.com/en/iphone_3g....asp?new_id=47
it claims to have the one and only sim turbo magic duel thingy!!!!

I have bought a PAYG O2 phone from the uk (still a virgin) and want to run it on the eplus network in Germany!

Help is requested, thanks!