Here are the books that I have. Price is $100 if you want everything. Otherwise look at the individual prices with a minimum $10 purchase.
Adult Master Chief Costume: $25
This is what I have if you want everything
Mass Effect Ascension (not sure if these top ones are HALO)
Mass Effect Retribution
Mass Effect Revelation
Mass Effect Collectors Edition:
All Mass Effect Books for $25
HALO The Flood: $6
HALO First Strike: $6
HALO The Fall of Reach: $6
HALO Evolutions: $6
HALO Contact Harvest: $6
HALo The Cole Protocol: $6
All six for $30
HALO Wars Genesis
HALO Graphic Novel
HALO Blood Line
HALO Uprising (four part series)
Gameinformer
The Art of HALO Creating a Virtual World
HALO Encyclopedia: $25