These are some of the online library resources for criticism and background informatio, along with a website for monologues:
Shakespeare for students; available online
Collection of essays by Shakespeare scholars that have been selected for students. Each entry includes an introduction; a plot synopsis; a character list; a discussion of the work's principal themes; information about the style and literary devices used; a conversation about the work's historical context; and a critical overview.
Shakespeare's words : a glossary and language companion, available in print at REF PR 2892 .C78 2002
Excellent source for understanding unfamiliar words and phrases from Shakespeare's plays.