I want to install a new system but I don't know what's the best brand
What type of amplifier and what speakers would I choose. Also where would I located all this in the car. I don't want wires hanging all around

 

Ur question can be answered in a million ways. There are a lot of good quality stereo amps and speakers out there. It all depends on how much you wanna spend. Me myself, I only use JL Audio subs and amps. But putting n a new sound system in these cars is not that easy

 

JL is going to be expensive but it is one of the best brands you can get for audio.
Kicker (for example) is cheaper and you can get more power for the price your probably going to spend (but not as good quality).
Yes putting in a new sound system in your car is not easy. If you want everything to work and look good. I recommend to get it professionally done. And doing that will cost more.
The more money you spend the better system you can get.