When i was in Asia, i picked up some burnt (copied) music CDs. Now i wonder if ripping from them using EAC would be as accurate as ripping from the original ? Or is the process of coping MUSIC CDs not that exact ? And do errors or differences from the original slip by ? As far as i know, coping DATA (not MUSIC) CDs is VERY accurate. But is it the same for AUDIO ?

Depends on if they used EAC

Yeah i figured that part, but i mean if you used CD Copy by Raxio or something similar to that.... would it make excat copies ? It would for DATA wouldn't it ?

It would for data but not necessarily for audio.

Yes, you can have some problems that had occured when they read the original before making your copy. They won't be detected when you'll rip it, because the problems would be recorded into the original extraction, then burned without errors in your copy.
They can show up as clics in the sound, and wrong track synchronisation.

Can someone tell me WHY coping AUDIO tracks can cause errors while coping DATA tracks are usually perfect ? Isn't it all just ones and zeros writin on a disk ?

Copying data tracks is not always perfect, it depends on the condition of the disc, and also the condition of the DVD/CD drive your using.

Data CD's have error correction data that audio CD's lack. That's why a CD has only space for 650 MB of data, but about 750 MB of audio.