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.
planet plant plaint planed pliant plained planate planned plenty palinode pollened pollenate pollinate polenta
planet flaunt slanty sealant reliant plant planed gleaned coolant callant gillnet gellant gelant volante volant leaned eluant leant ballonet alant lunet loaned linnet cleaned gallant plaint valiant pliant reloaned slant telnet