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.
down downy don dawn town dona done donne towny donna donee townie donnee townee den din dun ton dan dine deny tony dune dene dyne dino deni tone dean toon danio deign diene tauon tawny toney tonne
gown lown mown known own sown down town shown on