It's the same thing really. If you use the PIC18 series, the registers have different names but otherwise you should have no trouble. 2 Gotchas
#1: the direction register is TRIS instead of DIR and the direction is inverted. TRISA = 0 sets all of porta as output, PINA on the avr would be PORTA on the pic and PORTA on the avr would be LATA on the pic
#2: no fuses set in menus. the boot options are set in code with the #pragma directive (for C18). There is a very convenient help file with all the options for each MCU in "C:\MCC18\doc" called "hlpPIC18ConfigSet.chm", some standard functions like delay stuff is in "hlpC18Lib.chm", don't use the I2C in that help file that is bit-bang, you probably want hardware I2c
One thing you will love is not having to deal with that BV macro shit. Every PIC register a struct for the bits. for example,
TRISAbits.TRISA1 = 0;
sets pin 1 as output with a single instruction (compiles to a BCF instruction)
the best place to get a list of those structs is the header file for your device in "C:\MCC18\h"
Other than that it is the usual data sheet surfing to find the register names and register breakouts for your peripheral of interest. You will find the PIC peripheral registers to be less consistent than the AVR, they tend to change with each new generation of pics.
I really don't think you need a tutorial if you are proficient with the AVR, just go download MPLAB and C18 and go to work.
I know you said Pickit 3, I just want to reenforce that. I like the pickit 2 better like everyone else but it is close to useless at this point (part support) so don't be tempted.
Last thing is check out the official microchip application library, it is very nice to have a manufacturer supported library for all those complex things (captouch, usb, ethernet, etc.)