The following is written by Steve Sterling WA7DUH.
CHIRP is a free, open source tool for programming frequencies, tones and offsets into many of today's VHF-UHF radios using a PC, Linux or Apple computer and programming cord. http://chirp.danplanet.com/projects/chirp/wiki/Home
To program a radio using CHIRP, a special formatted file listing of frequencies, tones, offsets, etc must be IMPORTED into the CHIRP application, which will then use the file to program your radio. Creating the programming file (in CSV format) can be time consuming and error prone.
It is most handy to start with a file with many of the local area frequencies of interest, then add or delete to suit your own needs. Attached is a file I have compiled for my use .... you may find it useful. [credit: John Schwab WB7JON, who compiled the PDF]
His list in pdf format is available in this same forum.] It has most of the Southeastern Washington 2M and 70cm band repeater and simplex channels, plus FRS/GMRS, Marine, Weather (receive only) and SAR frequencies we might need.
To edit the file directly, it is easiest to use Microsoft Excel spreadsheet or Open Office spreadsheet IN CSV mode only. Don't let your editing spreadsheet save the file in it's "native" file format-- it will want to do that by default and will hound you. It must be "Saved As" in the CSV format that CHIRP understands.
You can also import the file CSV into CHIRP and use CHIRP to make your edits. Be sure to Export or Save AS your edits as a CSV file from CHIRP for future mods or use on other radios. The CSV file is generally rig independent. I use the same file to program my Yaesu 8800, Wouxan and BaoFeng radios.