How to add user input to determine a variable in a macro
 

I am trying to use macros to automate a budget workbook in which entries are
made in separate accounts and transferred at the end of each month to a
summary sheet covering all accounts for that month. Each summary sheet is a
separate sheet in the workbook and is named for the month.

My current stumbling block is to obtain input from the user as to the month
being summarized so that the summary data will be transferred to the correct
summary sheet for the month.

I am thinking of a list box or other control that would allow the user to
select from a list of months which would then be transferred to a variable in
the macro code.

Can anyone advise me on how I would go about this? I am using Microsoft
Excel Professional 2003.

As you can tell, I'm a neophyte at this, so I will appreciate all the help I
can get.