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.
saughy saugh sugh sough sigh savoy savvy sophy
saughy toughy roughy ugh saugh lough tough teugh sugh sough pugh rough faugh laugh kiaugh cough vugh waugh
sau haughs sauce saucy shaughs