[help] I have chosen a LED light strip, but how do I choose the power supply?

I have chose this led light strip that I want to use to light up a two car garage:

http://ift.tt/1JnxufJ]

They seem like they would be the single brightest LED strip on Amazon.

Now, I am trying to figure out what power supply to use, and I see that someone talks about 7.5amps being enough in their comments, and I see mention of 12V DC in the product specs, but how can I figure out how many watts I need?

Also, I see that it is 17mm wide. How do I connect the cuts I make? I see mention of a quick connector, but I can't find a 17mm wide quick connector.

Here is to hoping someone on diy has experience with LED Strips.

Thanks in advance!

Submitted January 23, 2015 at 12:56AM by a1reddit http://ift.tt/1JnxufE