netbeans - EJB : module and beans, project design -

this might noob question since starting project scratch, trying avoid wrong choices project design.

environment (constraints) : jee6, ejb 3, jpa, glassfish 3, maven, netbeans 7.

i have user service (register, login, remove, update, etc.)
have bank service (same idea...)
have bankaccount service links user , bank.
have operation service (add, remove, etc.)

i create 1 ejb per service. but, of services share (jpa) entities. mean must put them in 1 ejb module ? if must, mean have move whole module when want distribute 1 ejb service ?

basically, have domain classes (user, bank...) , service classes (userservice, bankservice...). services in ejb. ejb independent as possible. should put domain classes ? in library shared ejbs ? in 1 ejb module ? how organize classes ? (domain, services...)

also, know sites or books jee6 project design ?

thanks

regarding question sites , books ee 6.

i recommend have @ adam bien's website , antonio goncalves website.

both have written great books. adam has written "real world java ee patterns--rethinking best practices" , antonio "beginning java ee 6 glassfish 3" brought out book on ee 7