If you're looking for airline ground service freqs, ie baggage, ticket counter, ramp etc, those are often in the 460.00-462 or so range. At an airline's non-hub airports, they often use only one frequency for this and they're often the same at many cities. For example, United's is 460.725 in most cities where they only need one freq.
If you're looking for freqs that aircraft communicate to dispatch and ground stations with, I believe they're usually in the 129-132 range.
If you're able with your particular scanner, I'd suggest setting these ranges as your upper and lower limit and scanning all the freqs in the range. I'm able to do that with my Pro94, not sure if all scanners do that. That way, you can find individual frequencies and can often tell what carrier's it is by what they're saying. You can then write them down and program them to be scanned.
Matt