HOW TO CALCULATE THE LAST PAYMENT MADE ?

say there are almost 50 different clients and the names are written in column B and everyday i receive payments from different clients and the amount received stored in column G .

i want to retrieve the last payment made by a particular client say that is "abc" stored in column b3 to b50 and accordingly the pay amount stored in column g3 to g50.

kindly help

kanwal deep