Please tell me WHY Lit Agents here in Australia shun unknown authors? Simple question; simple answer is they are simply not interested in speculation with unknowns!
First, I have to say that the first statement is a SWEEPING generalisation. Literary agents don't shun unknown authors; we just have to be selective about how many of them we can take on. I certainly don't shun unknown authors - every author is unknown to start with, and I'd be pretty silly if I only relied on previously published authors to walk through my doors.
We have to be selective, though, because not all unknown authors are created alike. Some of them send in their very first draft and declare it the best unpublished piece of writing ever. Unfortunately, first drafts are never that. So when they are submitting alongside people who have been to Varuna twice, won the odd short story competition and are actively involved in trying to make their writing better, that first-draft writer is going to get rejected every time. Writing is a job as well as a craft, and the best unknown writers - the ones most likely to get published - are the ones who apply themselves to the task of getting published and are realistic about the workmanlike aspects of it. Agents can help - quite a bit, we would like to think! - but the writer also has to do more than just write their first draft. Yes, it's hard. But if you're good, someone is going to notice.
(It's especially difficult for first-time novelists, in particular, to get published because the obvious publicity hooks aren't there (as discussed below). But that doesn't we automatically say no.)
For an American perspective on why agents will and won't take on new writers, go to this link:
http://rejecter.blogspot.com/2006_10_22_archive.html and scroll down till you see the heading 'New Writers - Why We Seem to Hate Them'.