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.
stems steams stemmas stums sedums stimes stomas stimies stymies sodoms sodiums sodomies
items totems stems retems stums demos modems tams steams redeems teems reteams oedemas demes teams atmas deems atoms bottoms edemas odeums litmus datums toms diatoms adeems diadems shittims
stem stemma stemmy satem steam steamy stime stimy stoma stum stymie stymy esteem osteoma