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.
blabber blubber blubbery blaeberry belabor belabour bilberry blueberry bulbar
clabber blabber slabber slobbier slobber libber lobber lubber blubber blubbery flabbier flubber clubbier glibber globbier slabbery clobber slobbery clubber slubber