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.
assais assays asses assess assize
assais sis masas seis seas says saws sass phasis psoas assays hussies casas cassis gussies lassies lysis miosis meiosis tussahs oasis wussies whoosis gnosis nauseas nazis niseis poesies diesis missies poussies resaws cissies seesaws daisies visas basis bioassays hissies lyssas lassis quassias cosies cassias isseis bossies pussies physis ghazis fossas essays easies busies massas missays mesas tussis tassies dassies sissies sassies resays psis missis posies paisas noesis newsies naysays kneesies whosis chassis