You have a number of options:
1. Get an Elegant Bar Style speaker which would contain the front left, right, and center speakers in one cabinet.
Check out Leon speakers, and hide the subwoofer somewhere in the room.
2. Install Stealth Acoustics speaker which go under the drywall and are painted and feathered home, or Sonance makes these as well, they sound pretty good.
3: Mount downward angled in ceiling speakers for the fronts as well.