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.
spates spats spaits spades spites sapotes sopites spots spits septs zapateos speeds spodes spouts sapotas sippets speedos spitz spuds
opiates pupates spates pates chapatis tippytoes pities deputes pipettes puttees sapotes paupiettes repeats cowpats coapts capotes putties poetess spites patsy zapateos sopites patties spaits pats spades spats potties peats pieties deputies reputes tiptoes chappatis
spat spate sept septa spade spado spaed spait spit spite spot spotty sputa