If I decide to sell my Rift and Touch controllers what do I need to think of in terms of my Oculus account and the titles I already have in my library?
I guess the most important question is if I need to unlink the hardware in any way from my email address and account so the new person buying the gear will be able to use his/her own account.
You can use any account with any rift, they aren't locked. I've used multiple accounts with my home rift and my work rift.
However whoever you sell it to won't get any of the bonus software (Medium, Quill, Roborecall, etc) because each rift will only unlock the software onto an account once.