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.
spout spot sputa sapota sapote spotty sept spud spit spat spued spite septa spado spode spait spate sippet sopite souped speedo sped
pout copout spout pot put sapota teapot repute depute caput sputa capote sapote poet kaput kaputt pouty spot boughpot repot depot bowpot deputy putt wipeout