1) Listen to tonight's class, "Is it a Missvah to Live in Israel?" here.
2) See the sources we cited:
a) Ramban - Shikehat Asin 4
b) HaRambam - Hilkhot Melakhim 5:9-12
c) R. Hayim - Tosafot Ketubot 110b
d) R. M. Feinstein - Igerot Moshe EH I 102
e) R. S. Wosner - Shevet HaLevi 5:173
f) R. O. Yosef - Yehaveh Daat 4:49, Yehaveh Daat 5:57
3) Read an original teshuvah by R. Ovadia Yosef to the Prime Minister of Israel's office regarding this matter, here.