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.
cobra cobber cobbier cowberry caber cuber goober kbar
cobra dobra bra bura labra zebra bora brae braw bray labara goober libra librae lobar ciboria sabra sober dobro