Networking/Security book recommendations

[Dooling37]

Looking to get rid of this 'flooz' account that apparently I somehow have and is about to expire.
Found 4 books that looked interesting at B&N online:

-Top-down network design $55
-Hacking exposed $32
-Secrets & Lies: Digital security in a networked world $24
-The Cuckoo's Egg $6

I only have $10 of flooz, but willing to cover the extra. Probably looking for more of an educational book, so I'll probably skip 'The Cuckoo's Egg.'
Anyone read any of these -- opinions?
Or any other suggestions?

Thanks alot!