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.
cineast cineaste sanest soonest zaniest sunniest sinuosity censed sunset zinced zincite
cineast nest boneset keenest canniest honest ginniest neist veiniest fawniest boniest liniest bonniest fainest punniest renest piniest nasty finest sanest sunniest downiest dynast tannest teeniest tinniest unseat wannest wenniest whinniest sheeniest mooniest vainest leanest rainiest luniest fenniest gooniest canasta viniest honesty phoniest runniest funnest funniest looniest funest finniest hyponasty puniest meanest cineaste soonest zaniest dunnest dynasty tawniest tiniest toniest waniest weeniest whiniest winiest shiniest