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.
hallow hallo hollow halloo halloa halo hall hollo hullo hello hillo hallah holloa hilloa hulloa hulloo holloo hill haul howl hail hale heal helo hull hell haole helio hilly holla holly
allow tallow pillow fallow wallow hollow callow mallow bellow shallow yellow hallow sallow billow follow willow mellow fellow low halloa hullo holloo alow below tallowy billowy hulloa plow hello niello willowy blow slow holloa lilo alloy hallo hilloa blowy flow phyllo duello halloo pillowy hulloo hollo cello glow hillo felloe sallowy fillo jello yellowy