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.
grapey grapy grape gripey crape grope gripy gripe crepey grippy crappy grippe grappa crappie groupie grip crap gorp crepe crepy cripe group creepy croupe croupy creepie croppie
drapey grapey rape ropey frappe harpy crape crappy crepey grape grapy gripey sarape serape drape sharpy