HI I need Help Creating a Macro for my job!

We currently have two workbooks, one has multiple worksheets containing
invoice information. The other has one worksheet containing all of the
information of the other workbook.

We are double entering the information right now so I would like to run a
macro that will allow my entry on the first workbook be automatcially entered
into the second workbook on the next available line.

Can anyone help me???? Thanks!!!