My wife had a phone interview in the UK and was offered the job next day. That was 8 weeks before we were coming over. She is a nurse, and that industry is very sought after over here.
Depends on what your profession is but I was general and sales positions, I must have applied for several hundered jobs before we left, all unsuccessful due to people here like to recruit face to face where possible. I soon found upon arrival that you are fairly certain to get employment oif you are 1) hardworking 2) prepared to be a bit flexible, e.g. willing to accept a position even if it is not 100% the exact one you want.
Once employed you are then in a better position to assess the market and upgrade your position.
I was having a coffee while my boys were in the soft play area when I met a couple who owned their own business and offered my a position. Some things fall into place, somethings don't fit, but as Blunose states very well, you need to be patient and in time it will all come together. Good luck, and if you need any help once you arrive then we are all here waiting to help!;)