Okay I got it...

Dim lastrow as Long
lastrow = Sheet3.Cells(Rows.Count, 3).End(xlUp).Offset(1, 0).Row
MsgBox lastrow
' Message box shows me the first empty row number cell in the ID column, which is good I got something to work with...
then
Cells(lastrow, 3).Value = lastrow - 4
' the (- 4) is the offset of where my data started, meaning my data began being entered on row 5 and my ID numbers began on row 5 starting with 0001 so when the lastrow code above returned me the value of the next empty row I subtracted 4 form lastrow value which give me my next ID number in the ID cell where I needed it to be


I'm sure grateful for your help and direction...