How can I get my coin authenticated?

Mirrorcoin, instead of doing a long write-up here, let me just lead you to this page :

http://rg.ancients.info/guide/slabs.html

It tells you all you need to know abt the top tier, second tier, etc. third party grading services with their slab details, fees, and tons of other helpful info.

The top two services at least for now are PCGS- You will need a PCGS coin dealer to submit it for you and it is not cheap. As for NGC a dealer that belongs to the American Numismatic Association or a dealer who belongs can send the coin in for you. ANACS the oldest service with a great record in authenticating coins has a web site that you can down load there submit form, print it and send it in yourself. There prices are reasonable and you don't need a middleman. www.anacs.com I use them on coins that I want authenticated like a Fugio cent. Their grading is not bad either. ANACS is more for the average collect not the big shots, who may in the future see that did it wrong and will lose a lot of money.

The two top tier grading companies are PCGS and NGC with ANACS probably coming in a close third. I have never submitted coins to any of these companies but if you go to their web sites I'm sure you can get the specs on their submission requirements.

Unless the coin is worth at least $100 it probably is not going to be cost effective to submit it. You could always take the coin to a dealer and see what he says.

I would go to a place that sells/buys/trades coins.. maybe ask the person there.. he would know for sure.