You will probably need to do something like this...
System.IO.FileInfo finfos = (new System.IO.DirectoryInfo(Server.MapPath("~/Journal")).GetFiles("*.pdf"));
foreach (System.IO.FileInfo finfo in finfos)
However depending on how many different files you might end up with you might want to think about tracking each uploaded file in either a database or XML file.
Then you have the option of storing name, description, uploaded date, where it was uploaded from etc.