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.
fortis forties forts fortes frats frits farts fords frets ferities frites fruits fiords fritts ferrets fordoes fretsaw ferrites verities faradise foredoes ferrates phorates fritz fards verts varieties farads virtus frauds vertus veritas viroids verites virtues faradays faradize variates virtuosa virtuose virtuosi virtuoso virtuous
fortis irids worts mortise ferities frats treaties curtsy carrots girts hydrids brats carts reties pierrots gratis hearts writs crits rots bruts fortes murids carats grits ruts rets rotis vertus karats aortas turrets shorts charts whorts trets tortes tarts dirts sureties certes prats parties neuritis shirts frits jerrids territs derats purities parities marts rids korats verities quartes harts quarts hybrids sorties hurts garrets barrets boarts arts grids jurats morts ferrets brits artsy courts rats hearties parts grots airts cartes borts drats iritis carets curets torts forts farts merits worrits verts forties sciurids jerids burets quartos virtus kurtas varieties karts berets quirts orts pretties darts terrets frets trots cherts nerts parrots ports rarities sorts dirties tarots tortas treatise warts charities shorties yurts
fort forte forty fart fiord ford fordo foredo forrit frat fret fretty frit fritt