SSH, Unix commands & RegEx

This summer I am sitting in on a computational linguistics course. It is the first instruction I have had about UNIX. Pretty Awesome.
This has required me to do some googling looking from terminal commands.

This is kind of a sketch of where I have been.

UNIX:
http://www.osxfaq.com/Tutorials/LearningCenter/

SSH:
http://kimmo.suominen.com/docs/ssh/
http://ss64.com/osx/

TERMINAL:
http://homepage.mac.com/rgriff/files/TerminalBasics.pdf

grep:
http://www.thegeekstuff.com/2009/03/15-practical-unix-grep-command-examples/
http://en.wikipedia.org/wiki/Grep
http://www.computerhope.com/unix/ugrep.htm

Regular Expressions:
http://www.zytrax.com/tech/web/regex.htm
http://www.regular-expressions.info/tutorial.html
http://gnosis.cx/publish/programming/regular_expressions.html

RegEx and Unicode:
One of the issues that I have had with RegEx has been what is a natural class? i.e. [A-Z], [A-Za-z], [0-9], etc. As a linguist I deal a lot with IPA characters, subscripts, superscripts, unicode, and diacritics. How am I to define a natural class with these? Can I define a natural class based on the phonology of the language?

So I did some more searching:
http://unicode.org/reports/tr18/
http://unicode.org/reports/tr18/tr18-5.1.html
http://icu-project.org/docs/papers/iuc26_regexp.pdf
http://courses.ischool.berkeley.edu/i256/f06/papers/regexps_tutorial.pdf
http://wapedia.mobi/en/Regular_expression?t=5.

RegEx+PERL+Unicode:
http://perldoc.perl.org/perlretut.html

PERL:
http://www.enginsite.com/Library-Perl-Regular-Expressions-Tutorial.htm
http://www.cgi101.com/book/connect/mac.html
http://www.mactech.com/articles/mactech/Vol.18/18.09/PerlforMacOSX/index.html

Python:
http://www.amk.ca/python/howto/regex/