I would watch some of the "Spectate Live" games to get a feel of how to play, or load up a pro player video on YouTube. A couple champions I would recommend for a new player:
- Master Yi
- Ashe
- Alistar
- Teemo
- Tryndamere
- Xin Zhao
- Pantheon
These champions do not require much time to master and don't have too many complicated combinations or hard-to-master skillshots/builds/etc. I also tried to omit 6300 IP champions, but if you're willing to shell out $10 for a champion, there are some pretty nice choices out there. GLHF