A good generic place for a sub box is mounted in the trunk and ported into the back dash, if you want ports. Ports usually mean a larger box. If you plan to build it yourself, and you dont want a fiberglass enclosure, use 3/4" mdf (Medium Density Fiberboard). You can also mount your amp or amps next to the box or under the front seats and still have plenty of cargo room. If you buy one of those pre-made boxes make sure to check the intrernal volume of the box with the sub manufacturer's specs. I would check Crutchfield.com and also sounddomain.com for prices and specs. I have a pair of Kicker Comp VR 10" subs im my truck and Kicker has a guide on how to build boxes for them on thier website. By the way, they rock! good luck.