Yeh, some of those job forums can also make you a decent income, but it does take persistence, and persistence, and persistence - and a bit of guerrilla marketing=).

Like what sannbe is mentioning, it could be an idea to actively seek out such opportunities. And find businesses that might get asked for design work, but don't actually have a designer on-board. That's also where ITG and other freelancing sites can come in and help such businesses (or designers) outsource some of the work they cannot do.