I have the latter of those books and it is a solid text. It has a few handy utilities and some very good examples that I was able to hack up to my liking. The Roth website (author of the latter book) has lot of good information as well. He also has another book: Perl Scripting: The Administrator's Handbook that I would give similar comments about, not omg you gotta have it, but if you have the book, it is money well spent.