Yes, it's true that iPhone-ready docks and connectors also feature auxillary inputs that will let you play music from nearly any device. But if you want to reap the full benefits of "docking," including charging your Android phone, you'll need to try one of these two methods:
The DockBoss+ from CableJive is a utility cord that plugs onto any iDevice-specific 30-pin connector and snakes away into two Android (or Blackberry) ready plugs: An audio jack for listening, and a mini USB for charging. The 2.5-foot cable will start shipping out on September 28th for $29.99.
Until recently, DIY was the only way to go for users who wanted to plug their Android phones into iPhone connections. If you're handy with a soldering iron and want to get hands-on, check out these step-by-step instructions to creating an iPhone-to-Android adapter. If you're handy with Polymorph, the mouldable material used to shape this dock adapter's casing, you can even create a polished cradle for your phone to sit in.