First off welcome to my favorite obsession. Your friends are both right and wrong. Hops are added at different times depending on the flavor you wish to accomplish. There is no universal set time, each recipe is different. As far as a good book I would get "how to brew" by john j palmer ...
Congratulations I remember my first brew day... just know that this is the first step to an obsession that will consume your mind, wallet, and liver. There is not a better hobby in the world.
I know that I use a blowoff because I live in an apartment and can not risk an overflow in my unit. But I also do not see why it matters what setup someone uses if it is what they are comfortable with.