Excel 2007 : Doing Multiple entries based on condition

Situation:
I have 5 different worksheets.
Sheet1: 3 columns.
Based on a condition on the value of first column,
I want to copy the next 2 columns in different sheets.

For example,
if sheet1!A1 = Alpha , sheet2!B1 = Sheet1!B1
if sheet1!A2 = Beta , sheet3!B1 = Sheet1!B2
if sheet1!A3 = Gaama, sheet4!B1 = Sheet1!B3
if sheet1!A4 = Alpha , sheet2!B2 = Sheet1!B4
if sheet1!A5 = Beta , sheet3!B2 = Sheet1!B5
if sheet1!A6 = Gaama, sheet4!B2 = Sheet1!B6


I am finding problem implementing the incrementing of rows for destination

Try using
=INDEX(B:B,ROW(A1))

Instead of B1 to increment automatically.
Adjust accordingly for your sheet references