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.
prost prosit prostie prest porosity presto preset purist priest purest prosed periostea prosciutti pursuit prosody prosciutto poorest parasite prussiate pursed prised parsed praised prissed pressed proceed perused pursued preside persuade presidia presidio praesidia
frost prost lyrist corset roast queerest forest roust wrest grist rust fairest roset roost frosty crust nearest hurst prest verst rest airest purist rearrest serest sourest dearest direst drest tourist tryst worst sheerest horst first curst merest verist crest wrist aerosat burst erst aurist arrest aorist barest prosit karst frowst jurist horste querist verste poorest verset purest rarest searest sorest surest diarist dourest durst trust worset wurst yarest
pros prossie proso pross prose prosy presa uprose prase pursy proas purse prise prows parous prese pars parse perse press prissy priss purs praos pursue porous pyros porose uprouse