We cover a lot of languages and other topics in this course, usually not in enough detail for you to start programming right away. This page collects some useful summaries and tutorials to help you get going. Google points to lots more. Quality varies; if you find better ones to augment or replace these, please let me know.
AWK: my help file; vectorsite
Perl: my help file; Perl home page; Picking up Perl; CGI programming in Perl
Python: my help file; official tutorial; Python idioms
PHP: one, two
Ruby: one, two
C++: Doug Schmidt; functionx.com; STL by Jak Kirman
Java: my help file; Java Tutorial, with several books online.
C#: one, and many more.
Visual Basic: vbtutor.net; Visual Basic Tutorial.net
Tcl/Tk: one of several
Databases: my help file; MySQL; PHP & MySQL tutorial; MongoDB
Source Code Control: Pro Git book.
HTML, CSS, Web: W3Schools is usually the best place to start. Other useful ones include htmlcodetutorial, echoecho. CSS Zen Garden is quite remarkable. XML & Java from Sun
Miscellaneous: my gdb help file