Run Export Macro On Different Sized Ranges In Every Worksheet With Same Starting Cells?

I have a macro that I run repeatedly in a certain type of spreadsheet that does an export on a selection, pulls up a "Save As" message box and saves as a text file. There are 9 sheets in the workbook that contain the same data analysis for a set of samples, the only difference between them being the number of data (e.g. some may have 1500, 1400, 1600, etc.). I only select three columns of data to export (I6:K????) that contain counts (1,2,3,....), x-coordinates and y-coordinates. The counts column (I) uses a formula that only counts if there is an x-coordinate next to it (Col J).

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Generally, what I do to make quick work out of selecting the variable ranges is to select Sheets 03-11 (the first nine sheets) and select K6:I6 (starting w/ K6). Then, on each individual sheet, I do CTRL+SHIFT+DOWN to select all the relevant data (if I started my selection with I6, then it would select all cells that contained formulas which may or may not have x,y-coordinates adjacent to them). Once the data is selected (I6:K????), I run the export macro and save the data as text. I would like a macro that can automate the selection for each Sheet 03-11, excluding Sheets "all", "data" and "summary", and run the export macro, first prompting me for a file location and a file prefix. When the text file is saved, it uses the file prefix and Worksheet name to build the filename, i.e. "pathprefix_wkshtname".

I've attached an example workbook : 20120511_Au-cit_pH5_test.xlsx‎