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.
mattress mattrass matres matures matters matrass maters mitres madres metres mutters madrassa madrassah metros madras meters miters motors metiers meeters madrasa mooters madders maduros midairs meteors madeiras maderize madrasah moidores motorise motorize mudras
buttress mattress stress tress waitress votress tres trews coutures viatores headdress tries treys goitres tores matrass matres nitres sutures litres matures mitres readdress retires satires steres strass strews titres mattrass features tutoress metres votaress tyres attires tires address tares trees trues tressy trass cateress truss quatres duress natures poetries redress retries stares stores dress dressy futures shoetrees
mater matter mattery mature smatter