Amp, Sub system help wiring etc...

I was given a Dual XinBP 12" Subwoofer, 300w RMS, 550w peak, 4 ohms.
I have no owners manual or anything, and the company hasn't emailed me back yet.
Anyone know good dimensions for a sealed box? I've heard to leave at least 2 inches behind the magnet-i would like to make the box tall and not so deep so i dont take up too muhc trunk space.
Also what kind of amp would i need to power this?
I'm pretty sure i want to go with mono, but how many watts? (RMS or peak?)
Does the amp have to be 4 ohms as well?
What guage wire would i have to buy to wire this up?
How does it wire into the headunit?
Is there anything else i would need?Any/all advice is appreciated-sorry for all the questions-im new to car stereos-just wired up a new headunit and speakers and thats all the experience i have.

You're going to have to find the specs of the sub in order to build a good box for it. As for the other questions, you will need preferably a mono amp with anywhere from 200-350w or so, you can get away with less however. RMS(Root Mean Square) is what you want to look at. Peak means the amount of power the driver can handle for an instant but not a continuous amount. RMS is the amount that the driver can handle continuously safely. Im assuming the sub is 4ohm single voice coil, so you need an amp that puts out 2-300w rms @ 4ohm. Something like this would be good http://www.onlinecarstereo.com/CarAudio/ProductDetail.aspx?ProductID=16337You should be alright with an 8 gauge wire, but I would recommend the 4 gauge because you can upgrade your amp and sub later if you want and not have to run thicker wires. I like this brand http://knukonceptz.com/productMaster.cfm?Category=Amp%20Installation%20Ki ts pretty cheap and high quality.

To wire the amp, you must run a power wire to the battery, ground to the chassis, RCA cables to you head unit, a remote turn on the head unit, and speaker wire to the sub, probably 10 gauge wire will be more than enough.

i just got e-mailed back from the company- they gave me these dimensions for a sealed enclosure

24"w x 171/2" D x 13 1/2 H

does this sound resonable? it seems rather large for one 12" sub. maybe my calculations are wrong but that would be over 3 cu. ft....ive heard you only need about 1.7 cu. ft. for a 12"

Also, is there a peak and RMS rating for mono subs?

Thats about 2.8 cu ft. Seems pretty big for a sealed box. Every speaker has a peak power rating and and RMS rating. I couldn't find any other info on that sub since its part of a bandpass system. If you have decent woodworking skills or you know someone who does try building a 2ft sealed box and see what it sounds like. The box should only cost about $30 in materials to build , not including tools. But its much cheaper and you will get better results than with a prefab box.