That would be in your sidebar.php file inside your themes folder.
Just cut and paste it to the top of the sidebar.php file and then it will show at the top, not the bottom.
If you can’t find it then you must be using widgets and therefore you should be able to change the order of the widgets in presentation/design>widgets in your wordpress admin area.
When I cut and paste, it does not take, it defaults back to orginal settings. Additionally, below the sidebar.php is says it is not writable and I would not be able to edit it.
This is most probably because your sidebar/php is not writeable. You need to change the permissions on the file to 777. (CHMOD to 777). Then it should let you write to it.