Hi Brian,
All of sudden I had the idea to put a CHOOSE Formula into the Formula suggested by Narayan.
You can see the result in the file I have uploaded.
The trick is to first name your tables with the help of the namebox in the upperleft corner of your sheet. e.g. table1 for table1!$C$4:$H$14.
Then name the ranges for your MATCH FORMULAS. Since you will have two of the MATCH FORMULAS in a two way lookup it will be helpful to define the range of rows for the MATCH FORMULA,which will return the row_num in the INDEX Formula. Next would be to define the range of columns for the MATCH formula that returns the column_num in the INDEX Function.
Now you need a Number indicator that changes with you Data Validation list. To solve this I have put a MATCH formula in D4, which is like the one below:
=MATCH(C4,RANGE OF DATA VALIDATION LIST,0)
Now the CHOOSE Formula:
=CHOOSE(D4,table1,table2,table3)
That's basically how you apply the CHOOSE Function for your request.
The Final Formula is:
=IF(AND(C5>0,C6>0),INDEX(CHOOSE(D4,table1,table2,table3),MATCH(C5,CHOOSE(D4,Width_table1,Width_table2,Width_table3)),MATCH(C6,CHOOSE(D4,table1_header,table2_header,table3_header))),0)
Hope my long explanations somehow helped a bit to solve your question.
Mahir