Kindly provided by the Midd Philosophy Department, here are several useful websites that gather together many listings of undergraduate conferences, journals and summer programs in Philosophy.
A large clearing house for postings and calls for papers:
This site showcases several valuable summer opportunities for undergraduates in Philosophy, such as institutes, seminars, and research centers. Some of these would offer a grant or fellowship. From each link you can find out more specific information.
If you ever want to travel to participate in an undergraduate conference, there is funding available from the Office of Undergraduate Research. See the link below and apply for funding at least one month before the conference: