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.
first fairest frost fieriest firriest frowst frosty freest frusta forest frowsty fireside frisette furriest forestay verst verist verset verste farside varsity veriest feracity ferocity frizette virusoid
first eeriest leariest rest wariest mooriest hurst lyrist teariest arrest firriest burst grist hairiest poorest aristo barista aurist verist priest forest corset curst beeriest fairest furriest worst sheerest chariest wiriest tryst tourista durst direst sourest merriest crista arista cheeriest triste drest sorest barest purest verst rarest horst searest queerest dearest diarist veriest querist goriest crest frost prost verset wrist wrest airest prest hoariest aeriest erst aorist wristy tourist merest jurist nearest weariest rust leeriest burriest karst fieriest airiest serest horste rearrest verste purist wriest sorriest driest trust christy crust wurst miriest surest dourest tarriest touristy turista worset charriest yarest
firs fairies fairs fiars fierce fires frass frise frisee furs