converting data on import

[manatee]

I have a database that includes a city and county field. However, the data we imported uses "numbers" to link to another table (access database exported to excel) I would like to be able to import the main data, and then have a lookup/caalulation that essentially matches the numbers, then imports the actual city name. For example;

Table 1 city=22, County=2

Table 2 CityID=22, Name=Los Angeles, County=2

Table 3 CountyID=2, CountyName=King

I tried a "Let Function" but deleted everything (what I wouldn't do for an UNDO!!)

Sorry is this is simple. I just do not want to maintain the city, and county tables after import.

Thank you!