To get a National Insurance number, you'll need to go to one of the JobCentres (or call) and make an appointment. I got an appointment within a few weeks of when I called, but I wasn't really given a choice of when to show up.

They just told me 'so-and-so time and such-and-such place on such-and-such date'.

Luckily, I was free.

It didn't take too long once I was there.... although it seemed like it was something I could have easily filled out on my own...

I had to bring my passport, DH's NI number and they asked if I was looking for work (but they didn't need proof- just my word).
Pretty easy, but a bit of a hassle as you might have to travel to another centre to apply.
