I need advice on how to take the first step into programming.

I have a website (www.globalize-this.org), but it's mostly static and non-interactive.  I have become proficient with basic HTML, CSS, and Flash over the years, but I do not know where to start with forms and scripts.

There is so many acronyms being thrown around like PHP, Ruby, Perl, etc, that I do not even know which one of these books I should buy first.

My Goals are as follows:
1) Create a form where visitors can enter a "name" and "email" and have this information organized and dumped into some type of email list that I can use to send updates.
2) Create a community function to my website where visitors can sign up and become interactive members that can have their own personal page and upload pictures, etc.
3) Create a comment section on my website underneath pictures so visitors can leave comments.
4) Shopping cart functionality so users can purchase merchandise from the website.

I hope this gives enough information to point me in the right direction.  Let me know if I need to provide anything else.  Who knows the fastest way to learn programming for the hobbyist?

Thanks in Advance,
Jeremy

Thanks Bret for the advice. 

How about for cost?  Does PHP cost money somewhere along the line? 

Off the top of your head, do you know of any particular websites that has a good summary of the different technologies available so I can get a quick overview?

http://training.gbdirect.co.uk/courses/php/comparison_php_versus_perl_vs_asp_jsp_vs_vbscript_web_scripting.html

Brief verbs about most of the technologies

Then, more specific:

http://en.wikipedia.org/wiki/Perl
http://en.wikipedia.org/wiki/Ruby_on_Rails
http://en.wikipedia.org/wiki/PHP
http://en.wikipedia.org/wiki/JavaScript
http://en.wikipedia.org/wiki/Active_Server_Pages
http://en.wikipedia.org/wiki/Python_(programming_language)