You have said previously that the US has hundreds of agents just in New York whereas 'Australia has a mere handful of agents' - why is this? Is it only because the small market and our dispersed population? (Australia has a population of 21 million and NY 19 million). If this is so, then I assume there is no hope of having a significant increase in the number of Australian agents in the future?
This is an issue I was going to raise in a general post, but I'm glad to have a question to answer ...
The agents in NYC serve the whole of the US - the US publishing industry is centred in New York City, with only a handful of satellites elsewhere. So, while there are agents in other places, the bulk of them is in NYC, because they need to be. Australian agents are in Sydney and Melbourne for similar reasons, but obviously catering to much smaller numbers.
As to why there aren't more Australian agents ... The brutal truth about agenting is that it's a lot of work for generally not a huge financial gain. We all have to do it because we love it, and sometimes we have jobs on the side so we can keep doing it. The other brutal truth is that you pretty much have to come from within the book industry - from publishing or bookselling - if you're going to hang out your shingle and become an agent (unless you're going into an established agency), because you need to have the network of contacts amongst publishers in order to make a go of it. So for new agents to appear would mean that people have to emerge from the publishing industry and be willing to work on commission - knowing that they won't see income for quite a while, because getting books published takes a long time, especially when you're just starting your own list. In order to take this sort of risk, they'll need an independent income - but they've been working in publishing for years, and that's not a lucrative industry, so they're probably not in a great position to take a risk on becoming an agent. A salary usually looks more appealing than working on commission!
Additionally, being an agent requires lots of different skills, and a whole lot of ball-juggling, that requires a certain personality type - mainly extroverts, who are not normally found in captivity in publishing. You also need a high tolerance for disappointment and an ability to deliver bad news in a way that doesn't leave us sobbing in the bathroom at lunch.
So, in short: you're right, there's not much prospect of a significant increase in the number of agents in this country, although there's an increasing reliance on them by publishers and thus, necessarily, by authors. We just have to ask you all to bear with us while we try to get through our reading and manage our lists, because we so much want to see you published - we just need more help!