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.
crapped craped cropped carped creped creeped gripped carpet griped groped grouped crept crypt crypto corrupt
rapped bewrapped wrapped crapped rewrapped frapped trapped raped warped gripped propped harped dripped ripped draped craped cropped reaped carped dropped prepped tripped repped sharped
crappie crappy crap crape croppie grappa scrap scrape scrapie scrappy