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.
rashest rushiest richest reechiest
gashest poshest rashest lushest patchiest poachiest techiest dashiest richest pouchiest beechiest peachiest witchiest touchiest bushiest mushiest beachiest catchiest itchiest fishiest bitchiest achiest chest pushiest meshiest gushiest dishiest rushiest reechiest botchiest pitchiest washiest ashiest tetchiest cushiest leachiest gauchest chesty shiest shist chichiest
rashes reshes rushees rushes brashes crashes trashes