Оформил: DeeCo
Автор: http://www.swissdelphicenter.ch

procedure ChangeDBNavImage(DBnav: TDbNavigator);
 var
   i: Integer;
   tempGlyph: TBitmap;
   ExePath: string;
 begin
   ExePath := ExtractFilePath(Application.ExeName);
   tempGlyph := TBitmap.Create;
   try
     with DBNav do
     begin
       for i := 0 to ControlCount - 1 do
       begin
         if Controls[i].ClassName = 'TNavButton' then
         begin
           case TNavButton(Controls[i]).Index of
             nbFirst: tempGlyph.LoadFromFile(ExePath + 'first.bmp');
             nbPrior: tempGlyph.LoadFromFile(ExePath + 'previous.bmp');
             nbNext: tempGlyph.LoadFromFile(ExePath + 'Next.bmp');
             nbLast: tempGlyph.LoadFromFile(ExePath + 'Last.bmp');
             nbInsert: tempGlyph.LoadFromFile(ExePath + 'Insert.bmp');
             nbDelete: tempGlyph.LoadFromFile(ExePath + 'Delete.bmp');
             nbEdit: tempGlyph.LoadFromFile(ExePath + 'Edit.bmp');
             nbPost: tempGlyph.LoadFromFile(ExePath + 'Post.bmp');
             nbCancel: tempGlyph.LoadFromFile(ExePath + 'Cancel.bmp');
             nbRefresh: tempGlyph.LoadFromFile(ExePath + 'Refresh.bmp');
           end;
           TNavButton(Controls[i]).Glyph := tempGlyph;
         end;
       end;
     end;
   finally
     tempGlyph.Free;
   end;
 end;

 procedure TForm1.Button1Click(Sender: TObject);
 begin
   ChangeDBNavImage(DBNavigator1);
 end;