The lower control arm is $143.82 but you may need other parts as well.
http://www.trademotion.com/partlocat...layCatalogid=0
To see what's involved go to
http://techinfo.toyota.com/ pay your $10 and download the appropriate pages of the repair manual.
However, replacing the control arm means removing the coil spring. This is a dangerous procedure if you don't know what you are doing. In addition, it's not even remotely a 15 minute job, so doing it in the driveway isn't an option. If it was me, I'd also replace the wheel bearings, the struts, and anything else that was even remotely suspect, turns, or is made of rubber. Once you've done all the labour to remove the coil springs, replacing the rest of the parts is trivial and doesn't add much additional labour.
The various pieces (* means they could be suspect):
1) FRONT HUB
2*) FRONT WHEEL BEARING
3*) STRUT
4*) LOWER INSULATOR
5) COIL SPRING
6*) STRUT BUMPER
7*) UPPER INSULATOR
8*) SPRING SEAT
9*) SEAL
10*) STRUT MOUNT
11) KNUCKLE
12*) LOWER BALL JOINT
13*) LOWER CONTROL ARM
14) STABILIZER BAR
15) BUSHINGS
16) BRACKET
17) LINK