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.
hopeless hoopless hapless hipless hopples hooplas huipiles huipils
hopeless shapeless tapeless popeless pipeless sapless hoopless topless napless zipless soupless soapless hapless capless lipless peles tipless gapless wheeples hipless shipless