If you can shape your text file a bit to look like below..
REGEX=.*My Song Name.*
REGEX=.*The 10 billion dollar tune.*
REGEX=.*Song with no name.*
Then select/copy portions of it into the clipboard and running "SelectEx FROMCLIP" should select all matching items.
You'd need to install the SelectEx script addin first to make this work. [Command: SelectEx (extended Select command))
What might also be helpful is a texteditor that allows you to select columns of text to quickly remove/add specific parts from/to all the lines (removing the leading track number and adding the REGEX= prefix e.g.). Editplus will do, Notepad++ probably can do this as well.