If you want reconmendations for new gear. For a HU Id go 1)Eclipse 2)Alpine 3)Pioneer 4)Clarion 5)JVC
Front/Rear Speakers: 1)Focal 2)Hertz Audio 3)Infinity 4)MB Quart 5) Rockford
4ch Amp: 1)Audioson 2)Pheonix Gold 3)Alpine 4)JL 5)Rockford
Subs: 1)JL 2)Pheonix Gold 3)Infinity 4)Concept 5)Rockford
Sub Amp: 1)Audioson 2)Pheonix Gold 3)Alpine 4)JL 5)Rockford
This is only my opinion, I do not profess that I am an expert in any way shape or form. These are in order of my preference.
I know others will give you their opinions, which will hopefully lead you to a decision. I sugest you listen to as many setups as you can. Especially if you plan on putting a fair bit of cash into your new system.
Do you research. websites are a great source.