I've been building stuff like this since I was about ten or so years old... and I love it!
It's amazing how fabrication techniques have improved in the last few years. Inexpensive hardware, 3D printers, and awesome boutique electronics stores like Adafruit, SparkFun, and Seeed Studio have opened a Pandoras-box of Awesome.
Are you ready to build your robot? Please make sure to read through the entire Instructable before making any purchases - parts are listed throughout.
If you have any questions, let me know - I'll do my best to help. Want to see ROBOB (ROB-OB) in action? https://vine.co/v/hBhqD1ZQHLm
Ding ding ding... let's go!