It's pronounced "DEE-nah"; I don't like the pronunciation "DIE-na" - it sounds risqué.

I grew up with a girl with this name, and we all always pronounced her name "DEE-na", not "DIE-na". I know because when I was little I used to confuse her with another girl named Diana, and it would've taken me a lot longer to distinguish the two if their names sounded the same!

If it's Dee-nah it's Indian, if it's Die-nah then it's Indian.

I've always heard it pronounced Dee-na, not Die-na. I prefer it pronounced the first way too.