There are many ways to get into Android development - buying and reading Android books, visiting a plethora of Android-themed dev sites, navigating thousands of StackOverflow.com questions tagged with "Android," or even entering our book giveaways.
For visual learners, here's yet another one - a massive series of hands-on video tutorials amounting to almost 20 hours of footage. The series, created by TheNewBoston and mybringback YouTube users, and organized into a straightforward 200-video playlist by ChangingTheUnknown, contains tons of absolutely free content that, in my opinion, teaches using the best way possible - by showing you code. Lots of code. All the time.
I'm not sure experienced developers will be able to justify spending 20 hours watching these video tutorials, but for those starting out, they're just perfect. Arm yourself with some patience, persistence, and a few pots of coffee, and get ready for a [hopefully rewarding] journey to the depths of the Android APIs.
Here are 3 random videos from the list - for the rest, hit the full 200-video playlist here.