Thanks for the replies. Remember, I'm not the original poster, but instead bumped this thread as it was relevant.
It's just some non-valuable items, under 15lbs, that I wouldn't want to be lugging around as I might be moving about by bus to various locations before finally flying out. That's why just paying excess baggage at the airport isn't really an option. Would prefer to send this off now. Just some papers, a few books, some tourist pamphlets, etc. Nothing worth paying for insurance or excess shipping. Possibly Correo might be the best, I assume the least expensive option of the group. Unless DHL or FedEx are offering some decent rates too. I'll check out the options and report back here eventually. Just was looking to see what others have found recently enough.
Thanks.