For a great sounding system under $1000 shipped, I'd do the following:
(1)
Alpine CDA-9805 - $181 shipped from Crutchfield (includes installation accessories). Great HU as a foundation for the system with pleanty of room for expansion (three 4v pre-outs, XM-ready, and lots of tweakability)
(2)
Lanzar Vibe 438 - $133 shipped from Ikesound. The front channels will run the components up front and give them a [rated] 175x2. The rear channels will be bridged to the sub for [rated] 600w. I think the power ratings may be a little exaggerated, but you'll still get an honest 100x2 up front and 400w for the sub at 12V.
(3)
CDT Components - CL-61a - $150 shipped. Some nice components for the front doors at a great bang for the buck price.
(4)
Blueprint 1202 - $97 + shipping = $125 [estimated]. An Xmax of 16mm one-way and the ability to take 600w while providing top notch SQ makes it a great budget sub that will sound great and still be able to play pretty darn loud.
(5) 4GA Four Channel Wiring Kit from
www.knukonceptz.com - about $40 shipped. It includes everything needed to wire everything up (power, patch cables, speaker wire, fuse holder, fuse, etc.)
(6) MDF, screws, liquid nails, some accessories from
www.partsexpress.com (carpet, terminal cup, etc.) to build a custom box and amp rack - about $50.
(7) Sound dampening material for the doors, trunk, trunk lid, and, rear parcel shelf. Polymeric Mastic from
www.mcmaster.com - $15/sheet. 5 sheets would be way more than enough - about $100 shipped.
Grand Total Including Shipping = $779