Force visitors to leave their e-mail?

I have this website with a photogallery and I’d want it to force every visitor to leave their e-mail addresses before they get access to the photos and other content. Just like a simple login function but all these e-mail addresses should be remembered by some PHP script, so I could use them to send news and other important information about this website. Pretty much like a news letter function. The e-mails could then be logged into a simple .txt document or something.

However, I’m really not good with ActionScript, I barely know HTML and I can’t do PHP on my own and I am only going to need to know how to do this once, so I’d appreaciate if someone would want to help me abit. Payment is not problem, I can pay for the help I get if that’s necessary.