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.
griffs griffes griefs gruffs gravies grieves grievous kerfs curfs graves groves graphs carafes curfews garveys greaves grooves
griffs riffs tariffs sheriffs giraffes sherifs griefs truffes draffs serifs gruffs griffes ruffs rifs reifs raffs sharifs briefs ruffes shroffs
griff griffe grief grieve gruff gruffy