Some claim 'nither' is better, but I think it's just snobbery. I was taught to say it this way and would, but there's nothing wrong at all with 'neether' IMO.
You can get phonetic symbols here- http://users.otenet.gr/%7Epetermac/call/pron/type.html
I think you need to have a phonetic font isntalled, which you can get here:
- For Teachers