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.
whupped whapped whipped whopped wapped wheeped whippet whooped wiped whipt wipeout
cupped whupped pupped upped tupped supped dupped copped capped lipped topped pipped louped quipped hopped nipped pepped lapped duped repped couped rapped ripped wrapped sipped souped zapped dapped gapped whapped tapped fopped mopped hipped yauped knopped puppet jauped bopped napped tipped chapped mapped gypped kipped whipped knapped sapped whopped sopped popped happed shopped rouped lopped chopped piped zipped dipped kepped gipped wapped poppied chipped shipped yapped yipped ped