What are you planning on building?
A good book for starters is P.C. Cokers Building Warship Models.
It's a bit dated but it covers just about every part of scratchbuilding ships.
It shows up on E bay a lot.
Theres one there now thats in bad shape for 100.00. probably not worth it.
Also look at Model Warships Underway
Mostly large scale rc ship
http://wmunderway.8m.com/home/home.htm
A lot of times it better and faster to buy a fiberglass hull from a manufacture than to build your own.
Scale Shipyard, Loyalhanna Dockyard, PS Ships all are good places to ask questions.
You can use foam core, styrene, polycarbonate or even carbon fiber for building the superstructure.
A lot depends on what your building and if it's a static model or RC.
Hope this is of some help.
James