There is no better way to learn robotics and other technologies than building your own things. This project Glo0my shows how you can build your own 3D printed motorized Dalek. You are going to need an Arduino UNO, 2 DC motors with rubber wheels, an IR remote and sensor, and a few other simple parts to get started.
If you know your Arduino and robotics, you can always add additional components to build even more sophisticated Daleks. More info is available on Instructables.