I read something about having to notarize my ballot or signature...
No! Notarization is not required in any state or territory.
The Military and Overseas Voter Empowerment Act (MOVE) of 2009 specified that no state or territory could impose notarization requirements on overseas voters or military voters for any aspect of the federal overseas and military voting process. Nothing to fear, here!
Notarization is a process that varies widely by country. In the U.S., it is often asked that you have a document notarized and it is a quick and inexpensive process. No major research or translation is required. That is not always the case when you are in another country with a document in a language that is not their own. It might indeed be a very expensive and time-consuming process to have a voting document translated and notarized. The barrier would be so high that it would essentially stop voters from voting.
The law that governs voting for overseas citizens and military members stipulates that notarization requirements are not allowed.
What you may encounter, however, in less than a handful of states, is a requirement to have the Federal Write-in Absentee Ballot (FWAB) "witnessed" by another U.S. citizen. That is a much simpler process, which does not require translation or legal fees. The states that request witnesses on the FWAB are:
Alabama (2 witnesses)
Alaska (1 witness)
Wisconsin (1 witness)
The witness must sign section 6 on the Voter Information page of the FWAB.