Jake and probably Rachel's last name was Berenson. The others' surnames were never revealed.
The next series is Remnants. It says so in the last book of Animorphs (book 54) in the authors note.The Megamorphs were written DURING the Animorphs.
Tobias dissapeared and Rachel died.
As of my last update, there has been no official announcement of a live-action Animorphs movie being released. It's possible that there may be plans in the works, but nothing has been confirmed as of now.
Animorphs was created in 1996.
The last book, it never tells what happens to him.
The ISBN of The Hidden - Animorphs - is 0439106788.
The Sacrifice - Animorphs - was created in 2001.
The ISBN of The Experiment - Animorphs - is 0590762613.
I can only find the first one for sale and no mention of another one coming out.
The Separation - Animorphs - has 158 pages.
The Separation - Animorphs - was created in 1999-07.
The Mutation - Animorphs - was created in 1999-11.