i must admit for anyone new wanting to get into the pentest arena for employment it can be a long and very winding road,where do i look,which forums are safe which ones are bad,the tools needed,learning all the different languages needed,asking new people for help ect.
ive thought myself about becoming a pen-tester but i really dont have the memory or attention span to be able to keep up with the new exploits and tech which is being released all the time!wish i did tho its a awsome thing to be able to get into.
i just do a little here and there from time to time break into a friends network then change the password about make it harder and harder to crack port check ect.
i use bt3 live cd with a alfa network AWUS036H which i love its great fun playing around with even busted my girlfriend when using ettercap,driftnet,url snarf that will teach me aye ;)
hats off to the OP for asking about things tho id normally just come onto a site and browse for a while and jumping in answering tiny easy questions untill i got kind of accepted by the others (hopefully).
if the books you are wanting are to do with security and wifi then id look up in the torrenting world a man named TQW he does alot of these types of ebooks and is quite a skilled chap and if you find him on a torrent site then be nice he will find you pretty much any book you require ;) best of luck in your career in security all the best im going to go and carry on browsing again lol