Most of the time, hedge fund conferences are free to accredited investors. Managers will usually have to pay to attend, though in some cases, whoever is hosting the conference may offer free access to managers as well. Investors are free because generally speaking, the more investors, the better. Hedge Fund Managers usually don't mind paying, because in return, they get to offer their product to the ideal audience. But in answer to your questions, no, not just anybody can go to these things. You must have some sort of presence in the hedge fund industry.