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.
speed speedo speedy sped siped spued spied spaed sapped sipped supped soaped sopped seeped souped spud spado spate sapid spade spite spode sapote sippet sopite zapped zipped sept spat spit spot
speed peed ped mapped poppied japed hypoed roped pooped sipped biped leaped peeped hyped kepped gapped gipped coped lopped capped pied beeped wrapped mopped cupped raped jeeped copped spued speedy aped whipped yawped dapped yapped shipped tupped chopped cheeped tapped wiped whopped dupped whapped looped riped upped nipped toped seeped bopped knopped reaped sopped doped piped zapped spaed fopped gypped repped popped dipped gawped supped topped hooped taped whooped heaped wapped shaped cooped chapped lapped hoped louped happed sapped couped siped rouped kipped napped soaped speedo hipped yauped quipped oped rapped pupped pipped loped pepped ripped knapped jauped copied caped lipped hopped souped shopped sped moped gaped spied zipped duped tipped typed wheeped whupped chipped yipped
seep seepy sipe spae spew spue supe