I was reading an article on some site that said that copied cd's sounded worse than the originals? is this true or is there any difference at all cos I thought everything was converted digitally
Any time you copy something you risk the chance of lousing some data. There are many methods that are uses to prevent this and if small parts are lost during copying they can be rebuilt as it's copying (if the error is small enough). But a copy will never be as good as it's orginal. I don't really think you can (with the human ear) detect any diffrence though, so it shouldn't matter unless your a profficinal producing something for someone.
Most problems occur during the extraction process from the source CD. I've had experience with some drives that are very flaky when it comes to digital audio extraction.