To find local frequencies to program into Chirp, after opening Chirp go to these tabs...
RADIO > QUERY DATA SOURCE > REPEATER BOOK > REPEATERBOOK PROXIMITY QUERY.
TIP: When programming your radio, be sure to Download from radio before Uploading the file that you just created to the radio.
I know this seems unintuitive, but the software has to know which radio you are programming. It has to know what slots are available.
Also, IIRC, make sure you have the file that you have created ( the frequencies that you want) OPEN (where you can see it) when you upload to radio.