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.
cupeler cupeller coupler cupular copular capillary
cupeler applier tippler suppler speller peeler plier poler puler appealer paler cupeller coupler peopler repealer repeller replier rippler ripplier spieler supplier shapelier
cupel couple cupola cupula cupulae cupule