Hey there FutureDoc!
A few things to do:
1. Go buy the official guide immediately. Right now. It's here:
Link
This is the big place to start. Buy the book and read it cover-to-cover.
It's breathtakingly boring, but by the time you're done you'll know more about the new MCAT than 90% of MCAT teachers and 99% of pre-med advisors. Seriously.
2. Subscribe/Watch this thread:
http://forums.studentdoctor.net/threads/mcat-2015-discussion.1053559/
That's our 2015 MCAT discussion thread and I'll be putting a post up there every few days with info and advice about the new exam.
3. If you want to start immediately, buy the KTP set of books here:
Link
The Kaplan books come with an online activation that will give you access to three full-length exams along with some additional online practice materials and videos. Knowing Kaplan, they'll continue to add content over the months to come so that by the time Spring rolls around, those books will prove to be a good value. You could also buy TPR's set of books if you're really antsy for practice tests - they also come with an online activation for 3 full lengths. Paying
$150 for three tests is kind of steep but the TPR books also have a practice passage at the end of each chapter, which is nice.
4. Bookmark the Khan Academy link:
https://www.khanacademy.org/test-prep/mcat
The AAMC is partnering with the Khan Academy to provide free MCAT prep. For now, it just looks like they're doing content videos and not full practice tests, but still it's an amazing free resource. As it gets built out further, it looks like this website is going to make things like Chad's Videos and the Kaplan (et. al.) online pre-recorded video courses basically obsolete.