Thanks!
No, Iselin is Is-eh-leen or Ees-eh-leen, but probably most likely to end up as Is-eh-lin in my accent!
It's the Norwegian form of Aisling/Aislinn.
Eisley is eyes-lee, not ease-lee, and is supposedly a variation of a Swiss surname Eisele (same pronounciation) meaning cheerful.
http://www.behindthename.com/pnl/56287