so you are trying to move a large number of files and you send a command like this:

mv *.jpg /NewFiles

then you get an error:
-bash: /bin/rm: Argument List Too Long

this is how you solve it. instead you can send this command i use:

cd /home/user1/www/images
mkdir NewFiles
find . -type f -name "*.jpg" | xargs -i mv {} ./NewFiles

ok, let me explain what i did in the last three commands:

1. i changed directory where my jpg file were
2. i created a directory called Newfiles (this is where i wanted to move all the jpg image files)
3. execute the find command and save that list to move it to the NewFiles directory

thats it, hope it works