IF you wanna pay for them Itunes is always a good decision but if you dont and wanna be a pirate and i dont really recommend this u could look for some torrentz or use something like frost/limewire
How do you prove that we exist, maybe we dont exist
Get a video converter and convert them to mp4 and either use itunes or use jailbreak it and add the files in your self.
Not sure if itouch is mp4 only of videos tho =D
I have a itouch but the last movie I watch on it was Slumdog millionare.
If your into manga, jail break it and download mangadl from cydia. To bad you will have the updated verison tho, they are trying to go legit to dodge the government, so the new update removed naruto, bleach, and one piece =D