2 Baruch (highly recommended, especially chaps. 53-85)

4 Ezra (highly recommended, especially chaps. 11-16)

Apocalypse of Moses

Book of Enoch (highly recommended; especially Section II, chaps. 37-71)

Revelation of Esdras

Christian Apocalypses Links (Binder)

Not all in the list are full-fledged apocalypses, but most have some apocalyptic features.

Witherington, "What the Left Behind Series Left Out"

Witherington, "A Cracked Code"

Wright, "Farewell to the Rapture"