I've taken a list of English words, and examined each of them to see what they sound like (using the PHP metaphone function). This page lists the most common metaphone codes, along with their words. You can also search for a word of your own, and see which words sound similar - and which ones rhyme, and which ones alliterate.
fallacy flays falls fleecy fellas fallows valleys failles fellahs false fleys fells foals fulls fails fills flaws folles villas foleys flossy floozy follis floosy falsie fleece fillos filles fellies felloes fellows fillies follies follows phallus volleys
fallacy lacy lacey allays bullace cullays
fall faille fallow fella fellah