Here are the Gooligum baseline, midrange and enhanced midrange PIC Tutorials, previously hosted at www.gooligum.com.au, now all available for free.
A number of the introductory tutorials are also available as videos at https://youtube.com/playlist?list=PLrYikcedhNLTdxBoJWXIXXoKGwZsmFD_Q
The design files for the training board (designed for use with these tutorials) is available at https://github.com/gooligumelec/Baseline-PIC-training-board
The tutorials are being made available under the Creative Commons Attribution-ShareAlike 4.0 International license, which essentially means that they are free to use and share, provided that you attribute the original creator (me / Gooligum). See LICENSE.txt for details.
Note that in the time since the tutorials were written there have been multiple changes to the IDEs (MPLAB then MPLAB X), C compilers and even the assembler. And of course many new PICs have become available, although the core architecture, register and instruction sets have remained the same. Due to these changes, I am unable to provide any support.