Module development and code questions

I'm doing some research on CMS for creating community-drive sites. Drupal has been one of the best I've seen out there. However, I'm wondering if there is a module written for Drupal that allows a site-admin to email all the members of the community site. A project I am working on (for an alumni group) requires this functionality. I see the mail handler module which allows folks to update the site through email, but not an email list kind of functionality.

Thanks in advance!!

webform is a new node type that enables you to create forms and questionnaires for your drupal site.
You can use them to let the visitors give you feedback, rerquest information, place a order or registered for a course.
Get it here.

I was just curious if whoever was behind the development of the image module was planning on updating it to 4.4 anytime soon as it is a great module. Hopefully it's in the works already but I was just curious. I'm still learning PHP and might try hacking at a module when I run into the requirements.

I'm developing a module to attach files to a story. It means putting a link that run a set of function by clicking on it from the story form.
The problem is.. I'm trying to do simil as the node_image does (adding a button), using the _nodeapi function, but the output returned from that function does not appear in the form. Do I have to implement other functions to get what i want, and in general, how can I add more fields to an existing form whith a new module without modifing the one existing?

Is there a module that lets you set meta tags for all pages or one that sets pages for specific ones? If there isn't, where is a good place to start looking in how to do that? I need to put a pics label on all the web pages for my site and would love to be able to put a Creative Commons header for those nodes that have one.

I've set up the ECommerce module and it seems to be working but I can't figure out to add "inventory." My "products" (which are actually subscriptions) show "sold out" and I can't find the way to establish "inventory." Has my installation failed, is the tool hidden somewhere I can't find it or do I have to change the database by hand?