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.
card caird cared caried cardia cardio crud curd cred cord cart cardiae carried curdy cored garda crowd credo guard carat cried creed caret crude carte cured crowdy carate gardai carrot garred curred corody cruddy crowdie carroty curried corrody corrade corrode grid quarried crit grad curt kart court crate curet gored gourd grade greed gride grody cruet karat quart
bard card shard board fard hard heard hoard beard lard guard liard nard pard sard ward chard yard