I am running a complicated set of data tables; there is a data dump that needs to be performed fairly regularly. The only way to assemble the data dump involves joining data sets from two different (but related tables).

Since Filemaker doesn't support the 'append' function when exporting data to a text file, I am forced to perform two separate searches in two different tables, and do an import from both to a _third_, temporary table, and then dump all the data from that third table to a text file.

All three of these tables are in ONE Filemaker file.

Is it possible, when adding a File Reference to my import scripts, to use some kind of shorthand notation that means 'This File You are Currently In'. In other words, when specifying where to import the data from, I want the import script to know not to bother looking around for another file, just to use itself as the source.

That is, in essence, what you are doing when you specify the file from which to import by clicking 'specify data source', then 'add file', select your current file, and click 'OK'. There is no shortcut way around that.