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.
timbrel timbral tumbrel tumbril tumoral demurely
timbrel gambrel tumbrel whimbrel morel gomerel nombril sombrely timbral tumbril umbral
timbre timarau timber timbery timer