New Speakers

I'm curious what makes you want to go from having components to putting in Coaxils?  You'll get far better results by upgrading to an entirely new component set and being that you already have stock tweeters the install should be a piece of cake.  Trying to install a set of coaxils in addition to your pre-existing tweeters won't sound right and you'd be amazed at the sound improvement with aftermarket tweets.  I recently put the Polk db5250 5.25 component set in my '04 Grand Am and have been really pleased with them.  I would have gone with the db6500 6.5s but I was going to have clearance and fit issues so I went with the 5.25s instead.  I'm not sure if you made the coaxil decision based on cost or what, but you'll definately be more happy with a component set, and you can find them for about the same price if you shop around.  As always, the best way to find out what best suits you is to go listen to them, and Crutchfield is a great resource for doing research, but obviously their prices are a bit high.  I purchased all of my audio equipment (deck, front and rear speakers and sub) from ebay.  I've never had a bad experiance and I buy all my equipment new, not used but at much lower prices.  The 5250s list for $179.00 before shipping on  Crutchfield and I got them for $112.00 with shipping brand new on ebay.  Whatever you decide to do, make sure your speakers are installed right.  You don't have to have them done professionally if you don't want, just make sure you take you time and it never hurts to put some kind of deadener on your doors or at least around the speaker opening.