^^ This seems you have a strong belief in your faith, but your knowledge about your region is weak. or you maybe dont give importance to your books. or maybe you want to keep those books away from general public. which shows weakness in religion to me. anyways. dont worry.
Question: What are your future plans. like other sects 12rs and sunni believe in Mehdi, revival of islam, etc etc
the only thing that motivated me to open this thread is all the wrong stuff being spread about ismailis over the internet.. but there's one thing, my intentions r pure.. i guess america spoiled me.. n i asked my dad about ismaili books.. u can read nahj-ul-balagha of hazrat Ali (A.S).. or u can contact ismaili council of your city and ask them to provide wid books written by **ismaili imams n peers appointed by imams or the books approved by the institute of ismaili studies (which is approved by the imam).. **don't read books written by other people except for what is in bold.. farhad daftary is a twelver shia but his books r approved by the institute of ismaili studies u so can read them too..
Answer to your question: well, for us, imam-i-zamana is the mehdi.. imam jafar sadiq (A.S) has said : if there were two people present on earth, one would be the imam n surely the imam would be the last to die so that people may not ask Allah on qayamah that "why didn't you leave us with a hujjat on earth".
all this means that there's no one moment on earth when there's no guide present in the form of an imam (as ofcourse Risalat came to an end with Huzoor (S.A.W)..