I don't have any experience when it comes to audio systems so I was wondering if you guys can give me suggestions as far as what kind of amp (channels/watts) I would need.

I currently have the 4 in-boat speakers which are all 200 watts.
I also just bought a pair of tower speaker from my friend. They are 500 watts (http://www.amazon.com/dp/B0071HZJ56/..._M3T1_ST1_dp_1)

I eventually want to have a sub and add another pair of speakers along with some lights for the tower.

What kind of amp should I get (brands) that are good quality and what watts/# of channels should I be looking for?