My apologies if this is a little broad, but I'm struggling to know where to start here!

OK, so I have a Drupal site and I need users to be able to sign up for certain content, here is the workflow in detail:

I need a form within a block consisting of the following elements:

First Name (required)
Last Name (required)
Organisation (optional)
Email Address (required)

Then there will be a choice of content to sign up to (using checkboxes):

Policy Bulletin
Action News
eBulletin (which only members can sign up to)

Then the usual submit button of course!

Upon submission, users will:

1) Be taken to a confirmation page, or 2) Be informed about incorrectly filled in fields, and/or the need to become a user to be able to sign up for the eBulletin.

Users will then receive an email when new content of the type(s) they signed up to is created, along with a link to the node. There should be details about how to unsubscribe within this email.

I have used the Subscriptions module in the past, but I am not sure if it is possible to use a sign-up form with it. Plus, there is the added complexity that one of the content types, eBulletin, is only available for site members.

Like I say, I'm struggling to know where to start, and any ideas would be gratefully received!