Put these formula in your combined sheet (Summary) in the cells stated:

A2: =INDEX('store list'!A:A,INT((ROWS($1:1)-1)/(COUNTA('product list'!A:A)-1))+2)

B2: =INDEX('product list'!A:A,MOD(ROWS($1:1)-1,COUNTA('product list'!$A:$A)-1)+2)

Copy the formula from B2 into C2:D2, so that you have these:

C2: =INDEX('product list'!B:B,MOD(ROWS($1:1)-1,COUNTA('product list'!$A:$A)-1)+2)

D2: =INDEX('product list'!C:C,MOD(ROWS($1:1)-1,COUNTA('product list'!$A:$A)-1)+2)

Then you can copy these formulae down as far as you need to, and then fix the values.

Hope this helps.

Pete