software

I have some data that is pulled from another sheet and next to it a quot;location
reference numberquot; that is used to sort the data, I need for if a new item is
inserted in the source data and it is pulled into the sheet that the numbers
on the side stay the same...ref number data a data b data c3 a1 b1 c1
a2 b2 c2
5 a3 b3 c3
1 a4 b4 c4
2 a5 b5 c5

the data is pulled from another workbook, the problem is when this info is
updated and say a new item is now in between one of the previous ones the
ref numbers get mis aligned, basically I need the reference numbers to be
somehow tagged to the data so if it moves so does the location number,,
sorry if this is a poor explanation, and thanks for any help..