Hi! Registration Manager here! I think you may be the one who emailed us 2 days ago about this but we haven't got to replying to it yet so I'll try my best to answer it here.
Since you're 18, you will need a photo ID with a picture and date of birth. This can be a State or Federal ID such as a Driver Licence, State ID, Passport, Military ID, etc. We also accept work ID's and library cards that have your picture and date of birth on them (I have see those library cards before but they seem to be a east coast thing).
Unfortunately, we wouldn't be able to accept your ID if it doesn't have a picture. If you do plan to get a new one close to con (you still have plenty of time right now), we do accept the temporary paper ID's that the DMV gives out while you wait for the plastic one in the mail.
Feel free to email us at registration@kumoricon.org if you have any other questions or concerns.
Thanks!