Following links contain good tutorials and example codes developed in microchip C18 for PIC microcontrollers
http://www.mcuexamples.com/PIC-C-Examples.php
http://www.mcuexamples.com/PIC-LED-Example2.php
http://www.mcuexamples.com/push-buttons-and-switch-debouncing-with-PIC.php
http://www.mcuexamples.com/PIC-Relay.php
http://www.mcuexamples.com/PIC-Serial-Communication.php
http://www.mcuexamples.com/PIC-internal-EEPROM.php
http://www.mcuexamples.com/PIC-Seven-Segment-Displays.php
http://www.mcuexamples.com/PIC-C-Examples.php
http://www.mcuexamples.com/PIC-LED-Example2.php
http://www.mcuexamples.com/push-buttons-and-switch-debouncing-with-PIC.php
http://www.mcuexamples.com/PIC-Relay.php
http://www.mcuexamples.com/PIC-Serial-Communication.php
http://www.mcuexamples.com/PIC-internal-EEPROM.php
http://www.mcuexamples.com/PIC-Seven-Segment-Displays.php