Tips for my MMATS subs??? help?

Im buying 2 12" mmat P2.5 subs. any ideas on what amp i should buy?? and i dont wanna it to cost a nut sack plz. and also what are equalizers and crossovers? i saw them on sonicelectronix.com? if they make your system better then i want one! anything i should buy to make my system top notch??? tips plz!