Nope, they are not part of DDI Insider. If the current RPGA guide is telling the truth, though, it's pretty easy!
Get an RPGA/DCI number. At the moment, this means finding an event (either a CCG event or LFR, either works) and asking the organizer for a card. They'll give you one even if you aren't playing. Here's an event locator.
Register the number -- there's a handy URL on the card. Don't ask why you can't just get a number at the same Web site.
Click on the D&D logo currently in the middle of the page -- not the one that says Public Play.
Select D&D Private Event from the Event Type pulldown menu.
Click Next...
and follow the prompts from there; it should be pretty clear. Note that you have to select your module, then click Add to add it to the list before moving on.
Once you're done sanctioning and downloading your event, you can always cancel it if it turns out you won't run it on the day you expected. That's perhaps the easiest thing to do if you don't want to bother reporting it.
I'm sorry this is sort of a pain; the hoops are somewhat silly, particularly the bit where you have to get a physical card. On the other hand, you get access to something like 100 adventures for levels 1 through 14, all for free.