my subwoofer problem

You have a few options....you can do like your friend said and wire each sub in parallel, leaving you with two 2 ohm impedances to wire in stereo to a 2 channel amp.  Another option is to wire them in a parallel/series setup.  Keep each sub wired parallel, but from there wire the two 2ohm impedances in series to render you a single 4 ohm impedance.(what i would do)  Get yourself a good 2 channel or mono amp and you'll be set.     

Alpine PDX line of amps are a sure bet.  The PDX1.600 will you give you a rated 600 watts @ 4 ohms.  The PDX1.1000 will give you 1000 watts @ 4 ohms.  I like these because they give you the same output at 2 or 4 ohm loads, so if you upgrade your subs later you'll have a pretty versatile amp. 

I know I'll get some slack, but i like the Rockford Power series too.  The T600-2 will also work for you and gives you a few different options as far as wiring your subs.   600W bridged for four ohms, 300W x 2 @ 2 ohms, and is also stable in a 2 ohm bridged mode. 

Good luck and this should get you on your way...