rents in HK have always been high. but in the last five years or so they've become ridiculous.
IMO living out in the New Territories means commutes that aren't worth it. CWB/WC are good areas for the hobby but you may find better deals and fewer crowds in areas east of Victoria Park, like Tin Hau & North Point.
i assume you're used to the tiny flats HK offers in this price range, but here are a couple of URLs with lists of private agents. needless to say, you will need to call and check out the flat personally. many agents have several flats, so there's no harm in looking glum in a flat you like and saying "well, it's a bit small/expensive/whatever," the agent will say "oh i have another flat in TST, it's cheaper" and you say, "if i take a six-month lease, can you make it a little bit cheaper?" you won't get a massive discount but it's worth a try...
http://www.paylessroom.com/product.php?genre_id=6
http://www.paylessroom.com/product.php?genre_id=8
http://hongkong.craigslist.hk/sub/
JtB