Toyota Camry leaks oil?

So much more information is really needed for this but I will tr my best just the same. Most auto parts store sell a leak detection kit the comes with a dye that you pour into the fluid to be detected (oil in your case). You'll then use the uv glasses supplied in the kit along with a light pen provided with the kit to trace leaks. For best results, you'll want to run your vehicle through a car wash with an underside wash so you can see the fresh leak. Another way to go about this is to take the vehicle to a mechanic so they can tell you if the vehicle is worth buying and chances are they'll also do the same check described to you above.