The tweeter mounts are there, it's right at the base of the windshield on both sides.
But if you get components don't put the tweeters in the factory location. If you mount them more than about 8" from the actual woofer your going to having timing issues, lose your imaging, ect.
However for your needs, I'd get a good set of coaxils. Depending on the ones you choose will determine if you need an amp to power them. I heard a set of JL coaxils that sound great powered only by the stock HU.
If you get an amp, I'd suggest a David Navone LOC. Mine sounds great. (N7V,N-777,NE-7V)
http://www.DavidNavone.com
If you don't get an amp there will be no need to get a LOC.
Summary, go to your local shop, ask questions, get answers, fit within your budget and needs, make a decision.