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.
zips zaps sips zeps sipes sups sops saps ceps spas supes seeps soups soaps spays spues spies spews cepes spaes
hips sips ships chips whips tips dips zips rips gips pips nips mips lips quips kips yips