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.
pargos parks prigs progs parkas piraguas pirogues piroques perks porks proxy peroxy pricks percuss perukes porkies periques
cargos pargos sorgos largos sargos frigs farragoes burgoos burgs brags bourgs crags rags foregoes rugous grigs ergs argosy regs brigs aerugos frugs rigs drags drugs tarocs teargas trigs trugs cargoes crocs rocs rugose forgoes virgas viragoes frogs frags erugos viragos argus bergs progs grogs rugosa gregos rugs groks prigs rerigs narcos dregs durocs taroks trigos trogs shrugs
pargo park parka prig prog paprica paprika spark sparky