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.
grubbier grubber grabbier grabber crabbier crabber cribber curber crowberry
crabbier grabbier shrubbier ribbier grubbier cribber shrubbery crabber drabber herbier grubber grabber rubier rubber robbery ribier ribber orbier rubbery drubber robber