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.
dressily drowsily drizzly tressel doorsill dorsally dorsal dorsel tersely trysail hydrosol hydrocele tarsal tercel
brassily grassily prissily dressily reassail rosily horsily crassly crossly crusily greasily grossly prosily pursily drowsily
dress dressy dares daresay drees dries dross drossy dures duress tress tressy