Chicago has finally finished the massive Chicago Assyrian Dictionary, and it's all available to download for free in individual volumes. I've seen some Logos books recently with links to the CAD. Since they're distributing it freely, I'd like to see Logos look into distribution via Logos 
http://oi.uchicago.edu/research/pubs/catalog/cad/
A good companion and bridge volume would be this one. An Akkadian Lexicon Companion for Biblical Hebrew
Etymological, Semantic and Idiomatic Equivalence with supplements on Biblical Aramaic- Hayim Tawil.
http://www.ktav.com/product_info.php?products_id=2258 (Includes preview)