Copy formula until blank cell VBA

Hello,
I'm starting to learn how to use VBA (so bear with me!)

I have a column which has dates in it. The number of dates I enter into this column will vary so I need a macro that will go through this column, row by row until it reaches a blank cell (the last value).

When it finds a date in a cell it needs to insert the "=month" formula into the adjacent cell.

Example:

Column A Column B
27/10/2009 10
13/09/2009 09
30/07/2009 07

Macro ends.

Not sure if this is also possible but if it could enter the month name oppose to the month number that would be awesome. Seeing as I'm learning how to use VBA it would be really helpful if you could provide a few comments in the code so I know which bit does what :D

Thanks in advance,
Alex