Andrew,
You are right that most firms will hire a “known quantity” – someone who is recommended by someone they know.
I would also like to add something – I was the person who screened all the incoming job applications at one of my former offices – having a link to your portfolio may not be the best idea. I would look at and print any folios that looked promising so that the partners in the office could review them – they get too many emails and don’t want to be bothered to click on a link. Keep it brief and show only your best work. You should be able to make a PDF in a size that is email-able.
That said – it is just hard to get hired right now – you really need to figure out how to package your talents and who can use them very specifically.
Good luck.
Justine