Multichanger....

[carbonman]

I take it that you have put in amps before then?.........

Yeah fitted all the hi-fi in my old car.... if thats what u meant?

[rusty]

If you want bass get a Sub - it needs to be a minimum of 8". for best results go to either 10" or 12" this depends on what you actually listen to. if you listen to classical 8" is fine on the other hand if you listen to R'n'B, Drum & Bass, Thrash Metal you'll really need something that can handle low sub-bass frequencies.
If you still have the OE speakers and they are working fine DO NOT bin them. The stock Toyota ones are (front) 4" paper cone all range speakers @ 4 Ohms fitted into a purposely designed box which is ported.
(rear) 5 1/4" all range speakers @ 2 Ohms fitted into a purposely designed box which is ported & 2 x 3" Tweeters fitted into the rear headlining infront of the rear window.
,I, like you, want decent sound in my truck and having built sound off cars, fitted rucks of gear into my Artic, was not satisfied with the system that was already in place. I have looked at door builds, dash builds, boot builds and as Andy has said, sound deadening is a route to be followed.

In the end I opted to go with the OE gear, Why I hear you cry,
Basically because I couldn't face ripping the doors, dash,boot to bits just to fit stereo gear so I took a gamble and did it like this

Sony Head Unit with RCA Front & Rear connections to an Alpine 4 channel amp. This amp powers the OE speakers includin the tweeters in the roof.
Dedicated Subwoofer RCA to an Alpine 2 channel amp. This amp powers a 10" Jensen sub (my mate owns an ICE shop and I got it cheap!!)
I have up graded all the cabling including the power feeds

This system is LOUD, CLEAR and perfectly fine for all types of music.
I took it back to the ICE shop and they had a listen and the comments were "for a stock set of Amp'd up OE speakers - it's bl**dy good"

If you want some more help either go to a reputable ICE dealer (this does NOT include Halfords!!!!! ), buy Total Car Audio (bi-monthly mag) or if I can help I will. (ask Draig what it's like - he's seen it!)

I posted this ages ago for somebody else, may be of use......