Replying to Car Audio Assistance (Amps/Subs)

Not sure if this belongs in M/A or NSG but whatever, anyways I have been looking at an Alpine type R sub shown here http://www.onlinecarstereo.com/CarAudio/p_14954_Alpine_SWR-1242D.aspx

This model, another (newer) type R has less impedance. And is slightly sleeker.

I'm only buying one subwoofer.

I don't want to spend a ton of money on an amp so I am firmly set on buying this amp simply because of the price. http://www.amazon.com/Alpine-M500-MRP-M500-Amplifier-1-channel/dp/B0013TQ6FK/ref=pd_bxgy__img_b

My question to you guys is which of those subs will be best suited for the amp? Or will I have to pony up and buy an amp like this and break my budget?http://www.amazon.com/Alpine-M1000-MRP-M1000-Amplifier-1-channel/dp/B00142FJRC/ref=sr_1_1?ie=UTF8&s=electronics&qid=1293917346&sr=1-1

I have been reading things for hours about wiring and what not, and quite frankly I am confused and tired of deciphering what all this stuff means.

I will rate you 10/10 for whoever supplies coherent and valuable answers.