Posts #20 and #23 of this thread... and you're almost there... it's real simple... add to that the ADCIN section of your PBP Manual and the ADC Section of your chosen PICs Datasheet.

Lesson 1.

Get a PIC with ADC Input capability and enough pins to drive an LCD Display. Hook it up so you can send messages to your LCD. Put a POT (10K or 5K) across your 5v supply with the wiper to the PIC ADC pin. Write a small program to display what the ADC value is when reading 8-bit. Wind the POT up and down a few times to see digits change...

Lesson 2.

Repeat above with 10-bit ADC input.

You're an expert!