I am an excel newbie. I have a very simple table that calculates the VAT for me. Is there an easy way to 'fix' this formula to a whole column so that if i add new rows the formula still applies without me having to copy and paste the formula again?
If you are using Excel 2003, there is a feature called 'Excel Lists' that recognizes data in such a way that it can copy over formulas and formats for you:
http://office.microsoft.com/en-us/excel-help/about-excel-lists-HP001004433.aspx?queryid=d5372fc5ae3e4ea18232afc808f86682&respos=19&CTT=1
The same feature in Excel 2007 and 2010 is called 'Excel Table', which does away with the clearly-marked entry row, but assumes that anything typed into the next blank row is going to be part of the same table:
http://office.microsoft.com/en-us/excel-help/overview-of-excel-tables-HA010048546.aspx?queryid=3dcc9dafbc8242f4b195129eaf6f64fd&respos=5&CTT=1
If the formula only appears in a single cell, then you can use a column reference such as "A:A", which will refer to *every* cell in column A. Just be sure that you don't enter different data into the same column.
No, you can't add formulas to columns. You'll have to just extend (copy) the formula to as many cells in the column that you want. Just copy it into more rows than you think you'll need, then you don't have to worry about it. That's quite easy.