Don't try to get bass from a speaker
First of all, stay as far away from Sony and Bazooka subs as possible, they are total crap. A good entry level 10" sub with a good mono block amp will suit you just fine. JL-W0, Polk MOMO and Eclipse are some good subs to start with. If you're worried about bass output look for an amp with frequency adjustment knob. You can have enough bass to shake the whole car with minimal volume or vice versa. Also a good headunit with sub pre-outs should have subwoofer volume control as well as bass adjustment. Trying to get too much bass from your speakers will only distort your sound quality.
