Welcome Ignocio. This board is a lot of fun and an amazing resource for information. There are incredible posters here and I'm glad I registered.
As far as some good books,the default go-to one seems to be The Five Families by Selwyn Raab. If you are looking for a basic jumping off point for LCN history,this is a good one.
I would recommend Wiseguy by Nick Pillegi,the book that Goodfellas was adapted from,and Donnie Brasco by Joseph Pistone.
The Pistone book is way more detailed than the movie of the same name,and is hard to put down.
Both of these offer a true life account of day to day life in the Mob world. Wiseguy has some variation from the film,but when you read Donnie Brasco it's like a completely different story. In my opinion the book is ten times better than the movie and contains characters and storylines that were left out of the screen version.
I'll leave it to the other posters to share their favorites with you.
Again,welcome to the board and I hope you enjoy it as much as I do.