When do nav's begin and what's the process?

[LambOfGod]

I'm a student pilot and was wandering when a pilot begin's training for navigation. I know you need to pass the GFPT but what I dont know is;

• How many hours is the 'average' course?
• What theory tests are involved?
• Is it part of the PPL?
• When you complete your navigation, is that it, you have your PPL?

Thanks for any info you can give me. I know, I should ask my instructor/flying school but thats next week and for some reason I need to know now...