VBA Code to adjust for dynamic file name

Hi,
I am not an expert when it comes to VBA programing; however I often use the macro recorder, and delete items in the code that seem unnecessary.
Below is the code that I have.

The problem that I am facing is that the file name "NAV SHEET 070910" changes everyday.

The 070910 represents the date. The macro will not work unless the file is named "NAV SHEET 070910". How can I change the code to accomodate the changing file name.

Thanks in advance.

Windows("NAV SHEET 070910.xls").Activate
    Range("BA3").Select
    Selection.Copy
    Windows("Trial Browse.xls").Activate
    Range("F8:F24").Select
    Selection.PasteSpecial Paste:=xlPasteValues, Operation:=xlNone, SkipBlanks _
        :=False, Transpose:=False
    Application.Run "'Trial Browse.xls'!Start_TTrial"