Anode RGB LED Arduino Hookup Confusion
I had the same issue trying to use RGB LED that came with my kit.  

Indeed, all the examples for my kit were written for common-cathode RGB LEDs.  The PWM output values in the code assume common-cathode, and the wiring diagrams have the non-RGB lead wired to GND.  It took me some time to figure out that the LEDs I got were common-Anode, and that the non-RGB lead should be connected to VCC instead of GND. 

In adapting your examples, try this trick of inverting the scale just as your write the value out onto the PWM pins.  

 analogWrite(Red,255-x);
 analogWrite(Blu,255-y);
 analogWrite(Grn,255-z);


This nice thing about doing it that way is all the other example Arduino code out there written for common-cathode can be used basically as-is with just this final adjustment of the values written.