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.
castor caster coaster quaestor costar coster gaster gastrea questor gastraea gustier keester keister keyster kiester quester
castor questor pastor quaestor nestor juster mister keister moister history caster coaster muster visitor astir keyster bistre satori lustre ristra laster keester pastry maestri piaster master lister piastre rester wrester shyster wester waster toaster taster diester daystar zester sistra roster foster rouster meister roister vestry nester poster heister coster paster ouster leister maestro stour hoister ester star baster boaster bistro sautoir raster gaster luster oyster store bestir jester feaster story aster booster suitor stir pester faster costar jouster buster easter lustra roaster vaster rostra quester sister royster fester xyster bister rooster diaster duster kiester tester waister restore wastry chaster zoster yester
cast caste caseate cased casette casita cassata cassette caused coast cost costa costae gast