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.
repassed reposed repast reopposed rapeseed reposit rapist ripest ripost
passed bypassed repassed paused pissed appeased lapsed diapaused
repass reps reaps repays repos repose repps arepas prepays preps