If you go to this site, and do a "search" for GT40s, they have about ten books available
web page
Two that I think are really good are,
GT40 The Legend Lives On, by John Allen
Ford GT40, by Trevor Legate
Both of these books are full of color pics of real & a few replicas, and are very informative.
The Left Hand Drive vs Right Hand Drive has been discussed many times,,,and it really boils down to personal preference.
It will cost roughly 600-1000 dollars more to build a left hand drive car, which is not much when you consider the total cost of building a GT40.
One important thing to remember is that these sit VERY low, and it is the opinion of many (me included) that left hand drive is much safer in the USA, because it is tough to see around traffic if you are sitting on what is considered the "wrong" side of the car here.
I don't think a left hand drive version will hurt the resale in the US at all.