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.
brains brins brans burins bruins brawns burans brines bairns boranes brinies burns barns brens birianis brionies barons borons bourns beeriness browns bournes barrens byrnies burnous boreens barneys burnies baronies bareness burnoose baroness brownies baronnes brownness brownnose barrenness bronze bronzy
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
brain brainy bairn biriani borane bran branny brawn brawny brin brine briny briony bruin buran burin