VaisTech has an iPod integrator that allows you to operate an iPod via the stock audio controls as if it were a CD player. A side benefit is that you can get a free upgrade of the unit that automatically clicks on that stupid I AGREE button upon startup. So you never have bother with it again.
However, if you're not using an iPod or another MP3 player, this is an expensive ($200-$300) way to get around pressing that button.