In the UK the Night Goblin infantry (in strips with spears and squigs) are still available.
The old Night Gobin Archers have not been avaialable for a loooong time.
I echo Azrael's position. If you can afford it, buy what you need now because the entire Warmaster range is likely to very suddenly disappear down a black hole at some unspecified point in the future.
I am currently toying with the idea of buying the last army that I really want for Warmaster (I own 7 large armies) but do not own yet, a large (4K+) Vampire Counts army but it is a horde army and would cost me over £500!
Dave