If I remember correctly I believe the average car lighter is only designed to output 15 amps. I would check your fuse box to see how much current your lighter will let through before blowing.
You might be able to use
this amp. Even after shipping it should come in just under $100. Another amp that was recomended to me just today is
this, It should also come in under 100 after shipping
I plugged the stats into winISD for your sub and it looks like you about have to put that sub in a small vented box. At .25 cu^ft tuned for about 38Hz you need a 2in port almost 15in long ... and you hit -3db at about 42hz but it should be ok due to cabin gain in the car I would assume.
Im a relitive newb to others using winISD and box design so I would recheck those numbers before you go building anything.