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.
broader boarder brooder broider braider broodier broidery border birder breeder barrater brattier bordereau barter bordure bruiter barrator barratry barretor barretry brighter
broader broider warder trader prouder parader marauder guarder grader reader readier boarder border braider raider broodier brooder forrader harder hoarder carder corder crowder grodier larder order prodder reorder treader yarder
broad brad board braid bread bready brood broody byroad abrade abroad