You can typically mount crossovers in the doors with the speakers to minimize wires running into the doors, or you can mount them somewhere else, in the dash, kickpanels, under seats (not reccomended: water, trash, shock exposure)

As far as recomending a set it really depends on the characteristics of sound that you like as well as your budget.

The best thing is to personally audition a few sets of component system speakers at your local retailers. Bring a favorite CD of yours to listen to instead of thier music. Also pay attention if theyre playing the speakers with an amplifier or external sound processors. Most retailers would be glad to help any potential customer find exactly what theyre looking for. A happy customer means good referrals to them, so dont be afraid to ask and tell them what youre looking for. Then you could always come here for a honest or second opinion.