Append And Update Expense Query

I have an expense table and I want the expenses to be written to a new table every month, quarter, half-year, or year depending on what the user has selected. I want to group the expenses somehow and I want it to show all monthly expenses, then show which ones have +1 month. All those will get put into a append query and added to a new table that stores all the expenses from hence forth.

Alright, I have started to figure it out ( a problem from earlier) but I think I need some help. I want an if statement but I am not familiar with date functions. In an append query I want to look at my original table and add records if it is past a certain date.
For a monthly expense (entry date is 01/01/2006)

If (dateentered) month, +1
Then write the record.