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.
knot knout not knotty knit nowt note nota nod nut nit net neat node nodi newt nite gnat nett knead kneed natty netty nitty noddy nutty