For philosophy stuff, I always go to the Stanford Encyclopedia of Philosophy. Writing a SEP entry is considered quite prestigious, so they generally get some of the very best people in a given field. The SEP tends to be much more reliable than Wikipedia, though it's also often more technical. SEP articles generally concentrate on giving you a survey of the positions on a topic, along with arguments for each. The best ones are written dialectically, giving you some sense of the questions guiding the development of people's views.