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.
stull still stall stella stilly stole style sotol stale stela steal stile steel stool setal stele styli settle steely stelae stelai sootily steelie stoolie
stull atoll still ritual retell outtell mutule mutuel mutual dull tulle dully tule toll till tell tall stall medulla