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.
gratis greats groats grates grits grads grots grids korats griots greets grouts grides grades crates gradus kraits carats krauts karats curates garotes karates grottos creates garrets carates garottes grottoes garrotes keratose crits karts carts garrottes gourds cartes courts kurtas cruets quirts curtsy greeds curets carets quarts guards caritas carrots quartos croutes curtsey cardias curtesy gourdes curites quartes corodies corrades corridas courtesy cowrites crowdies curettes keiretsu queridas
gratis ratos treaties reties varieties fortis deaerates parties carts riatas karates hearts gyrates pirates harts greats karts raids phorates ferrates mortise kraits laureates drats charts treats tarts derats sureties narrates farts orates warts quarts grates serrates rats prats carates purities creates cerates rates reatas aerates hearties ferities frats berates karats rotis verities parts iritis groats korats boarts carats parities darts forties variates borates traits marts lariats braids curates arts rarities crates pretties jurats prates brats seriates krauts dirties urates neuritis erratas muriates sorties derates hydrates treatise charities shorties
grat grate crate grad grade great grit gritty groat grot grotto grotty