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.
fairest first fieriest firriest forest freest fireside furriest forestay frost frosty frusta farced frowst farside veriest frowsty feracity foresaid foreside frisette frizette verst forced frized verist verset verste frizzed varsity
airest fairest direst rest eeriest beeriest airiest furriest merriest leeriest queerest crest hairiest breast barest firriest forest poorest aeriest rearrest priest rarest searest sorest sourest dearest dourest driest teariest wariest wiriest charriest sheerest mooriest prest burriest reest presto purest nearest preset wriest hoariest miriest merest leariest fieriest goriest reset resat surest veriest serest resit freest wrest first sorriest arrest drest tarriest truest weariest chariest cheeriest yarest
fairies fairs farce fares fires