Recommendations for a User/Membership Plugin for managing downloads?

Here’s what I’m looking for. I’m trying to create a membership site that:

• Lets users select items they want to purchase from a “Store” page (or similar)
• Makes the item available as a digital download (i.e. presents a download link)
• Creates an account for the User, where the user-table stores the different products they have already bought. This way, if the download is interrupted, or if they lose those volatile digital files in a HDD crash, they can always download the files again.

Can anyone recommend a good membership plugin that could be configured to do this?

I’m not necessarily looking for a cookie-cutter, cut-and-paste, help-me-because-I’m-too-lazy-to-figure-out-how-this-works solution here; I am completely willing to learn, to experiment, and generally to make sure I don’t wear out my welcome with knowledgable volunteer help 🙂

That said, I would appreciate it even if someone just directed me to an internet article about “choosing a membership plugin that does x, y, and z”, or “configuring x-plugin to do y”, if the resource is applicable. Even a recommendation for a book would be nice…
At the bare minimum, I just require a starting push in the right direction.

Can’t wait to see what fellow users come up with…
Thanks in advance, guys!