i drive a 99 alero 4door n just got some new subs from a friend
theyre some cheap mtx 12" road thunders and i need to get wiring for them
i was wondering how much speaker wire i should buy and if i should drop the extra 30 cents a foot for some 12 gauge instead of 14.

Drop the extra money! Everybody always overlooks the wiring! They will go out and buy expensive subs, expensive amp, expensive head unit and wonder why it sounds like crap! Get the good wiring to support the system you are running even if you don't think it is worth it.