Copy & paste between open workbooks

Can somebody help me with code for this please?

I need to copy data from H20 on workbook A and paste it in the next available cell on Workbook B

Workbook B is always open.

im guess im missing something really simple here.... lol

Sub saveprospect()

With ActiveWorkbook
ActiveWorkbook.SaveAs Filename:="Z:\NEW PROSPECTS\Completed Prospect forms 2010\" & Range("H20") & ".xls"
End With

With Range("H20")

.Copy

End With

With Workbooks("prospect database 2010")

Range("A1").Select
Selection.End(xlDown).Select
ActiveCell.Offset(1, 0).Select
ActiveCell.PasteSpecial


End With


End Sub

thank-you