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.
groins grins groans grains groynes garrons grans goriness crones greens crowns kroons croons coronas gurneys carinas cronies greyness guernsey grannies guaranis guaranas greenies carrions grayness carns kerns corns kirns karns curns guaranies greenness kernes cranes cairns cornus querns carneys carnies corneas currans korunas careens corneous crannies
heroins groins grins girns carrions herons barons bruins coronas neurones cairns brines irones gyrons rains garrons frowns hyperons browns burins mureins brains brins parians marines marrons croons bairns shairns durians chorines turions dourines tronas triens pirns terrines taurines pereons prions purins drones morions sorns mirins sciurines serines kroons sarins murrains morons firns roans horns paranoias ruins rinse morrions virions frons neurons heroines jarinas irons crowns maroons rins borons neurines airns reins corns grains farinas crones girons marinas carinas morns porns murines pyrones kirns sereins saurians merinos serins moraines drains purines pereions groans durions terrains perrons trains trines diurons trones urines drowns chorions shrines
groin grain grainy grin groan grown groyne