What amp should I get.
How many subwoofers and what type/brand
With some loud speakers. Who can help?

Step 1) Increase budget.

Never heard of that brand.

If purchasing with a low budget like that. i would recommend looking on Sonicelectronix they have basically have everything from top of the line stereo equipment to the cheaper stuff. if you go on that site you can find a package deals that will give you everything you need for your car. Make sure you type in your specific car as well.

with a 500$ budget look for used gear on craigslist. . I find badass deals all the time.. my most recent was 2 12 inch mtx 9500 12s 4 200$.. I spent 120$ and built a box and sold em 4 600$.. not that ur gonna resell just pointing out deals.. but if u want good bass on a budget.. sundown SA series are nice for the prjce and so are american bass xfls

Couldn't be happier with my SA10's ;P