Sub Enclo for 8"

I would go for a front firing and stay away from bandpass unless you know that's what you want. Always sounded unnatural to me. Sealed or ported, or if you can, build something funky like a tapped horn. Check out the Tang Band 740 over at Parts Express. Good little workhorse.
Tang Band W8-740P 8" Subwoofer | Parts-Express.com