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