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.
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fattest hottest wattest phattest coattest attest wettest fittest test ruttiest dotiest zootiest mutest cattiest meatiest haughtiest pettiest jettiest rattiest bittiest doughtiest goutiest poutiest nettiest battiest gnattiest nattiest retest whitiest nuttiest chattiest testa tattiest fattiest neatest hootiest pottiest sootiest dottiest footiest matiest rootiest mitiest latest duettist peatiest tautest detest cutest featest testy guttiest knottiest quietest whitest wittiest nittiest shittiest