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.
sagas saigas sags sagos sacs zags segs skas skuas segos sikas socas sakis sakes sacks soaks segues squaws sax sukkahs sequoias secs sics skis suks suqs
agas sagas ragas ags gas gigas biogas cacas pacas reggaes raggs nags magus loggias laogais peags jaggs vigas quags jags sagos saigas daggas dags tags takas togas shags yogas ligase megass kakas mags fags kagus hags quaggas geegaws lags gewgaws bagass gaes gays goas bags kaas rags vagus gags sags zags dagos degas taigas teguas wags yags yugas