This is my Ardoaino ttp229 library!
Copy the "TTP229" library folder to your /libraries/ folder. Restart the IDE (close and open again).
Then in Arduino IDE: File -> Examples -> TTP229 -> KeyToSerial. File -> Examples -> TTP229 -> Calculator.
Follow the connection instructions at the beginning of each sample! In addition I've included a picture that illustrates the connections.
Enjoy :)