Living in Europe

So I'm planning on living in Europe in the new year. My cousin is living in London, and I would like to experience living there as well. My first choices would be Spain and Greece, but I'm also interested in France, Italy and Portugal. Could anyone tell me how to go about getting a job there? I have experience mostly in restaurants and I can speak basic spanish, but anything would work for me. As well, how hard is it to find a place to live and for at what cost would it be?