Module development and code questions

I'm a musician, and I'm a long-time programmer, electronica and Perl being my respective poisons of choice. I've built a large application-based site from scratch in PHP before, and I've dealt with a lot of OO-programming in Perl... so though I haven't delved into the codebase yet the design decisions in the handbooks I've read seem to make a lot of sense.

I've been trying to come up with a good system for paid and subscription download of my music, without reinventing the wheel, and without sacrificing the user experience by using too many disperate tools at the same time. Regular shopping cart software fails, subscription software and services fail, and there isn't even a good paid product that meets this need (Not that I'd pay, I'm a good ol' OSS cheapskate!). Oh yeah, and I'd like to sell tangible goods and music downloads at the same time!

I want to get my hands dirty making a Drupal module, and I have a need for a song module for Drupal that meets the following requirements:

1. Free low-quality sample previews of all songs
2. Paid or Unpaid (settable per-song) download of the full high-quality version of the song (purchased by adding to the existing e-commerce module's shopping cart). I understand that this probably means I will have to create a product AND a song seperately.
3. Users with a certain level of paid subscription are allowed access high-quality versions of flagged songs
4. Cover art with each song, a thumbnail on the song page with the ability to click to view the full version. This will default to a global image if none has been set for the song
5. Ability to add lyrics, copyright, links and other misc text for a song
6. Story-like ability to have a succint version of the song in a song list, and the more verbose version as a result of clicking a "read more" style link
7. Comments

Bonus options I may go for:

Hello Drupalers,

I have begun my first module development, one that displays a block for a node showing a link to a translation website (that translates that particular node).

So, I am actually having trouble understanding how Drupal modules know what node id is being displayed. For example, if "mysite.com/node/143" is being displayed, I want "function mymodule_block()" to know that the node id is "143". How do I pass that information to mymodule_block()???

Thanks! A very simple example would really help!

Hi...

I'm developing a new module and I need to use the image library in order to make thumbnails with GD.

Where can I find information about its API?

Thanks in advance

I'm looking at a query in syscrusher's hof module (I want to make it display vote averages and point totals in conjunction with moshe's node moderation module) and seeing something in the syntax I see often, but can't seem to find an explanation for:

$sql = "select n.nid,n.title,c.totalcount from {node} n left join {node_counter} c on n.nid=c.nid...(long line of stuff)..."

In this instance, specifically, the "n" in "n.nid", and where the "n" and "c" appear relative to the left join statement.

I'm new to Drupal. I'm trying to create a family website and I need to use the events module. I can't seem to find clear instructions on how to use it after it's installed. Could someone please provide me with a step by step guide on how to install the events module (just in case I missed a step) and how to use it to add new events and show them on the front page.

At a request I've created some files to integrate/use PRADO pages in Drupal. Included are a user class so the Drupal user works as a PRADO user integrated in it's security system, and from PRADO one may take advantage of Drupals security/user system. You may create regular Drupal menu items pointing to specific PRADO pages in the form ?q=prado/modulename/pagename (path configuration changeable). My client (and I) would like to contribute this, but I'm not sure how appropriate it is, PRADO not being Drupal and all.