Oh now I get it.... you want it to automagically grab the last file? http://www.sqlservercentral.com/articles/Log+Shipping/62676/ has one type of solution for this.

Optionally, not necessarily preferably... you can use xp_Cmdshell and Dir the directory and do something clever with the output (i.e. parse out the timestamp etc.):

Insert myFileListTable Exec master.dbo.xp_cmdshell 'dir c:\Backupfiles\'

This blog contains a solution http://blogs.msdn.com/stuartpa/archive/2005/07/21/441468.aspx that avoids xp_cmdshell and having to parse the output.

http://www.codecomments.com/archive352-2006-1-786972.html has some other options involving scripting.

HTH!

/Elisabeth