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.
foolish fluish flash flesh flush ghoulish flashy fleshy flitch filch fleche fleech fletch
foolish polish coolish dullish bluish bolshy bullish fluish ghoulish hellish golosh owlish palish relish delish dollish mulish tallish