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.
hydrase hydras hydros hydrous drays druse draws duras derays drowse douras durras yttrias dourahs drys dors dears toras dares trass torse tyros terse doors deers tahrs dries trays duros durrs drees dures doers trace tyres dorrs dorsa dross dress dories terais triose drossy duress terras deairs derris torahs torose drowsy dressy dairies dearies derries diaries dowries durries terrace
hydrase rase urase duras drays hydras druse wrasse braise erase fraise phrase crease grease raise praise prase reraise draws gyrase urease ras
hydra hydrae hydria hydriae hydro