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.
lysis lyses lyssas lassis lassies luscious lusus loses leses lases lassos lycees looses lasses losses louses leases laicise lassoes lessees liaises loesses
physis lysis sis whoosis sissies dassies psis cissies cassias missis posies oasis isseis tassies wussies hussies kneesies phasis hissies miosis quassias physes cosies cassis niseis bossies easies lassies basis lyses meiosis poesies noesis newsies gnosis missies seis lassis gussies assais busies poussies pussies sassies daisies diesis tussis whosis chassis