Sounds good. I may upgrade my speakers in time as I just used ones I had lying around from my last car.
I had Alpine SPG-17C2 2way 6.5" coaxial speakers in the rear and SPG-17CS 2way 6.5" components in the front. I have a 12" 2500w Alpine Type R sub in the boot.
I used these for the speaker door mounts: http://www.amazon.co.uk/gp/product/B005JZ8CK6?psc=1&redirect=true&ref_=oh_aui_detailpage_o01_s00
My amp is a 5-channel JBL GTO-5EZ which cost about £200 but I cant remember where from. Would have preferred an Alpine 5-channel amp but didn't have £500 lying around at the time.
I used KnuKonceptz 4gauge wiring kit, 5m triple shielded RCA cables and about 15m of 12gauge copper speaker wire. All these from amazon.
I have a Pioneer AVH-x8500bt HU. Cant remember where I got that but was about £400-£500.