When you talk of off-camera you will have to condider a couple of things.
1, How far away from the camers you want the flash.
2, How much control you want to have over the flash.
If you just want the camera off to one side and to use use the ETTL functions, that is the camera talking ot the flash, then you would need an off camera cable (1metre as sold by Flash at a good price).
If you want to move the camera further away but retain all the ETTL function then you would need something like an STE-02 (Quite pricey). Or use a second flash such as the 580EX which can be used as a master on the camera and "slave" the 430EX off the camera (even more pricey)
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If you want to move the camera further away but not use the ETTL then the radio triggers are one option. Using the trigeers you set the flash out put and lose all ETTL functions such as the auto exposure and automatic internal zoom facility of the the flash head.
The Upside is you can use any flash for experementing as it does not not need to be Camera specific - DO NOT connect any NON-Compatible flash directly to the camera.
The last option is to use a remote flash activated trigger, its a device with a photo diode window which triggers the flash when it sees another flash from e.g the pop-up flash on the camera.
For useful info check out the Strobist web site, it has many good acticles and an A to Z guide to flash photography in easy steps.
