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.
loon loony loonie looney loin lown lone loan lion leone lin lino lune leno line liny lien lane linn lawn lain luna lean luny lanai lauan lawny liana liane liney llano
boon coon goon loon moon noon poon soon zoon toon shoon on