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.
sheet shit shut shat cheetah shed shot shade cheat shott shoed shoot shied shoat shout shote shute shooed shitty chetah chaeta chaetae shittah chat chit shad shod
sheet het beet feet haet heat heed keet leet meet deet weet wheat whet cheat
sheesh she shea sheugh shew shoe sheuch