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.
speak spake speck spec spik spica spick spike spiky spoke spook spicae spikey spooky seppuku spic
apeak speak peak pack speck paik peag peaky peck peek apeek bipack copeck kopeck kopek repack spake peke shoepack
spa sipe spae spay spew spue supe