How to get cue audio through earphones/headphones ?

The headphone cue is actually managed by the dj software you use.
Usually to use it you set up one audio out in from the audio card for the main audio and another for headphones cue, then u can use the itm dj cue buttons to enable and disable cue in the dj software.

Is it possible to use the music on my ipod touch and itunes without a dj-program?

All iTM app are midi controllers,they are intended to control any kind of midi software.

As such iTM DJ is not intended to use your music inside the device.
Can i use the ITM DJ with the virtual Dj?/

You can test if iTM is compatible using our free iTM MidiLab

I have itm dj and itm midi can u tell me how to make it work with reason?

Our controller should be setup in reason just like any regular controllers 
or in mcu case like a regular mackie control unit.

Unfortunately we dont have a running copy on my machine to be able to provide u the detailed steps as we would like to.
But you should go to midi preferences and enable the itouchmidi ports
for mcu look for any control surface setup.

We would also advise you to take a quick look at reason doc regarding midi control, it is usually the smallest chapter in docs.

Is there a setup guide to get itm dj and Traktor pro connected?

We advise you to download the available itm dj templates available for download from our website.

You will find a template for traktor and traktor pro,
just import it and u should be set to go ;)