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.
groped grouped griped cropped gripped groupoid carped craped creped crapped creeped gript carpet
roped groped drooped trooped warped larruped reaped repped riped grouped rapped creeped cropped gripped ripped chirruped propped griped burped cirriped sauropod syruped dropped trapped myriopod uropod pereopod bewrapped rouped prepped trouped torpedo dripped frapped pereiopod harped carped craped chirped tripped urped crapped wrapped rewrapped cirripede siruped draped raped creped sharped
grope crop croppie gorp grape grapey grappa grapy grip gripe gripey grippe grippy gripy group groupie