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.
frowst frowsty frost frosty first frusta freest forest fairest forestay firriest fieriest frisette furriest ferocity verst verist verset verste farside varsity veriest feracity fireside foresaid foreside frizette
frowst roast roost roset roust aerosat frost frosty frowsty horst prosit prost worst
frows frowsy frowzy faros froes frouzy froze vrows