At a minimum you'll need to raise the front wheels, with a jack and stands, or ramps.00 Camry i4.
Would I have to lift the car up on all 4 tires to get to it?
Would this tool do? http://www.harborfreight.com/14-in-38-in-drive-long-reach-dual-flex-head-ratchet-67994.html
I already have a O2 sensor socket.
With modern quality ratchets, breaker bars are obsolete. The square drive will fail on both before the mechanism in the ratchet breaks.
I prefer either of these two for high torque applications. The extendable ratchet is nice if there's no room to hold the head of the ratchet, but the flex head is handy when you don't have a straight shot at the fastener.
If it's been a long time since it's been removed, snip the wires and use a regular deep (preferably impact) socket. Use your 02 sensor socket when you install the new one.