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.
grittily greatly greedily curtly courtly curtail griddle quartile cordially gradually cartel curtal kirtle
ruttily grittily prettily rattail rattly artily brittly fruitily heartily dirtily tartily shirttail
gritty grit griot grotto grotty