The MLA Handbook for Writers of Research Papers is the official handbook to MLA style. Although there are many helpful guides to MLA style you may have to consult the handbook for some issues.
The library has copies for checkout and in-house use. There is also a large print edition available for checkout.
The short videos on this page from Rutgers University Libraries are funny, but very informative. If you have any question about when you need to cite sources, please watch them!
MLA Handbook by