There's also an excellent (non-free) book: Definitive Guide to sed http://www.sed-book.com/ http://www.sed-book.com/ I found it to be well worth the money, t

There's also an excellent (non-free) book: Definitive Guide to sed http://www.sed-book.com/ http://www.sed-book.com/ I found it to be well worth the money, though I wish it were available as a PDF.