totally newbie in off camera (for wedding)

Hello.
The only way I've used a off camera flash was using two 580ex (master and slave). As you can see I'm full ettl user, never use manual flash.
My question is: Which equipment do I need to use only one 580ex (off camera) and has better range than Infra red ?

Second question is: I know I'll have to use my off camera on manual. Is easy to control the output power from my transmitter?

Thanks!

if not infra red, I'd say your next choice would be radio transmitter such as Pocket Wizards, Skyports, or the new Alien Bee CyberCync remotes.

As for you second question, if I'm understanding it correctly, you are asking how easy it is to control the power... if that's what you are indeed asking then it's pretty easy, on the 580EX II at least, it's a matter of pressing the Select button and rotating the dial to pick your desired output.

...but i don't think there will be a way to control the power from the transmitter. You will have to go over to the flash and dial it in. What I usually do is set the flash to a power, then control exposure with ISO and/or aperture. In some cases I have to go over and dial the power in to a different setting.

I would look at the radio poppers. I believe they transmit the e-ttl information wirelessly.

Radio poppers are probably the best option if you need to control flash power from the camera. Otherwise you'll be in manual flash.