I think the first question every aspiring writer should ask themselves is: Which type of publishing is the most compatible with me?
They should look at different ways of putting their work out there: self-publishing; small publishing houses who are willing to take unsolicited manuscripts and of course the big publishers, where one stands no chance without an agent.
I’m not suggesting this moment of self-reflection to dissuade you from the agent hunt. However, I firmly believe that our every step towards publication should be conscious and well thought out. You shouldn’t start to look for an agent because somebody else told you so, but because you’re fully aware what the advantages and disadvantages are and you want the deal.