you want to be paying a little more money for your speakers, or you'll be disappointed. I used to be like "I just want a sound system better than standard, nothing fancy."
But in the long run, better speakers, like Alpine or inifinity, etc, will be a much better choice. Anyway they arent that much more expensive. Another thing, it is best to grab a set from the new line (2008) so it has the newest tech. Check official websites of Alpine, etc.
Stay away from cheap speakers and stick to the big brands.
LL