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.
whisht whished wished washout whooshed wecht washed waucht washday wooshed watchout
whisht shat shit shot shut bowshot cushat licht mishit reshot
whish which wish wisha swish swishy