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.
speired spired spiered supered speared speered spored spared spread spoored spurred spiroid sparred zippered superadd spirt superette superroad sparid spirit sparoid sporoid sport sprit spurt sprat sporty sprite sprout seaport support
speired peered chippered diapered supered spiered speered repaired appeared capered coappeared coopered coppered paired lappered lippered loppered papered paupered peppered rapiered reappeared speared kippered spired zippered tapered choppered
speir spear speer spier spiraea spire spirea spiry super asper aspire