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.
fools foils foals fouls fowls folles follis folios foleys floosy flus follies fils folious foliose floosie follows flews fells flees floss fleys feels filos fails fuels flues flaws fills floes fleas flies flows voles flays files viols falls false fulls violas floozy voiles fillos ghouls filose fellas flossy filles falsie fellahs volleys felloes flossie fellows feeless fellies fillies failles fallows floozie vowless ghoulies
fools cools shools wools mools tools pools cowls fouls bowls floosy reoils knolls roles haoles foals lolls polos molas coles dols holloos cols polys toils viols kolos bolos oils polis sheols cholas wholes tolus dolls solus soils joles foils violas fowls molls diols howls noils kohls hulloos toles goals polls roils bolus aiolis soles voles mols colas koels loos boles pols solos holes jowls quolls kolas bolas bolls moils coils noels tolls moolas loose ghouls poles oles nolos boils halloos souls coals tolas moles gaols owls rolls sols doles hols cholos shoals yowls
fool flooey flooie foal foil foley folia folio follow folly foul foully fowl ovoli ovolo