old school again
 

i just got a rather "cheap" car off of e-bay and the car has no esc, but uses a second servo to adjust the throttle. it moves this little metal thingy on a metal disc plated with gold, and that's what makes it move. anyway, i want to upgrade it now and i have some questions. First, i want to upgrade the receiver, but it needs to run two servos seperatly. what kind of receiver should i get? (my budget is pretty tight, so keep that in mind) should i get an ESC? if so, what kind? i'm already using a Titan 12 turn motor in it, and i don't want to change that.

Thats called a MSC aka mechanical speed control.. and your 12t motor should burn it out in no time :) . Grab any 2 channel receiver you want but definatly get an ESC

Boy Howdy that is OLD school! What car do you have? AE 12E? The old wiper resistor will not hold up to a 12 turn motor best to upgrade now.