Virtual Salt
Virtual Salt: Word Roots and Prefixes
At this website, there is a large chart that "Contains some of the common roots and prefixes that make up the building blocks of numerous English words." Columns for roots/prefixes, meanings, and examples are included.
AdLit
Ad lit.org: Root Words, Roots and Affixes
Familiarity with Greek and Latin roots, as well as prefixes and suffixes, can help students understand the meaning of new words. This article includes many of the most common examples.
Other
Vocabulary Workshop
This vocabulary workshop will be helpful to anyone interested in brushing up on their skills. This site features a comprehensive look at root words, prefixes, suffixes and more.