How to measure 120 V, 60hz with an oscilloscope?
First of all, be very careful with playing with voltages from outlet. They are deadly. 

Next, your oscilloscope probe already has what you need. The generic ones, that you receive with you measuring device, most probably have a switch for x1 and x10. That's attenuation, not amplification. So if you switch it to x10 and feed 110V into it, you will read 11V on your scope. Now change the probe attenuation at channel setting to x10 and you will read real value of the signal. Be careful with your oscilloscope max. voltage specifications if you are in area with 220V coming from the outlet.

Second way would be to use a simple voltage divider and connect to your scope with x1 attenuation.