#1
I'm looking to buy this PA system
http://www.guitarcenter.com/Harbinger-Mains---Subs-Package-600623-i1373232.gc#

my question is do i need a mixer or something to power the speakers or will i be able to use it right out off the box

07 Fender American Deluxe Strat
07 Fender Custom Telecaster
09 Seymour Duncan Pickup Booster
09 Fulltone OCD V.4
10 Ibanez WH-10 V.2
09 Splawn SuperStock
10 Jet City JCA-20
97 Fender Hot Rod Deluxe

Yeh the SICK! bit sounds a bit stupid.

#2
Those are unpowered speakers so you will need an amplifier. You will also almost certainly need a mixer. You can get powered mixer, which has both. There are a number of things to pay attention to, including making sure the amp is the appropriate # of watts for the speakers.

FYI, another way to go is amplified speakers.