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.
haars hares hears hoars hairs hoarse haeres harass hearse hearsay harrows harries hers heres hours horsy horse hoers horas heros heirs hires hirees heresy heroes horsey houris horahs harissa heiress herries hoorahs hoorays hurrahs hurrays hurries
haars maars ars coarse lairs knars lears pharos bars hairs varas roars parse pares varus cares cars hoars rares ares laris gears bares gaurs mars pairs tears tiaras saros shares charrs vairs charas wears dares wares airs nears tares tars maras dears parrs soars gnarrs nares hears vars bears hearse knaurs saris oars fares tahrs paras souaris wars faros tarsi marse hares paris jars arse pears pars hoarse boars fairs naris mares shears carrs chares liars lars lares guars gars carse gnars raias mairs fiars chars ears feuars fears rears sears deairs taros wairs chairs years
haar hair hairy hare harrow harry hear hoar hoary