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.
umbel
umbel mel pomelo comely bumble fimble amble pummelo rumbly ramble sambal pumelo fumble mewl smell dumbbell namely tamely mumble timely gambol tumble kummel meal humble wambly chimbly nimbly pommel jumbal jumble mell homely camel gimbal humbly gimel pummel rumble rambla cymbal tymbal numbly samiel nimble symbol mumbly dumbly lamely timbal gamble tombal gamely wamble wimble shamble