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.
grains grans grins groins groans goriness grayness guaranas guaranis grannies guaranies cairns cranes greens garrons gurneys carinas currans groynes greyness crannies greenies carrions guernsey karns corns kirns carns kerns curns greenness kroons cornus croons crowns kernes crones querns careens carneys carnies corneas coronas cronies korunas corneous
rains brains grains murrains terrains trains drains pyrans guaranas boranes puranas groans rinse piranas brins marinas furans currans mirins carrions prawns durians ruanas mureins lorans sciurines bairns neurines murines jarinas farinas firns yarns shorans shairns chorines urines trines trans tarns dourines sarins purins parians cranes burans brans terrines saurians morions learns heroins carinas serines morrions virions brawns sereins airns moraines kirns darns reearns sarans harianas roans karns groins prions rins furanes carns cairns earns birianis ranis merinos pereions reins barns purines serranos durions heroines guaranis bruins ruins marranos marines girns pirns brines serins taurines grins terranes burins grans triens turions warns chorions sharns shrines yearns
grain grainy gran grana grannie granny grin groan groin