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.
pens peons peins penes penis peans peens pensee paeans paeons pennis peones pins puns pans pons peonies pennies panes punas pains pones pence pians pansy pines pawns poons pinas pions pannes pianos pinnas ponies pawnees pinnies hyponeas hyponoias ponce
bens kens sheens wheens weens teens wrens fens hyphens hens gens keens ens lens queens liens hymens miens peens pens rouens dens tens wens whens yens
pen penna pennae penne penni pennia penny