You'll want to use a PAC, as it's the easiest way to get the output for your amp. There's a thread in the How-To section for this. Even though you don't have the Bose system, it should be the same as the Bose How-To, because you still have the TAU to drive the infotainment screen.
As for speaker ideas, you should check through the audio upgrades stickie for some ideas. If you're putting in your own amp though, the sky is the limit and crutchfield.com should have speakers that will fit for ever bit of money your wallet has to offer.