- Should I get my cards graded?
Depends on your purpose. Mainly, the purpose most people have for getting cards graded is to increase the value and liquidity of their cards and to have a reasonable assurance of grade and authenticity. That this has become a widely-accepted practice attests to the value many people ascribe to professional grading.
The criterion typically used in deciding to get cards graded is whether the benefits are worth the cost. To determine whether it is worth the cost, you need to know the condition of your cards, the market value of the cards in each grade, and the costs of getting your cards graded (namely, the grading fee, the shipping and insurance costs, and the time/effort spent in the process). It is especially worth getting your cards graded if they are in "Gem Mint" condition, which commands a significant premium; however, this grade designation is very hard to obtain (and especially so for the grade above that, "Pristine"), and you shouldn't count on your cards obtaining this grade unless you have closely inspected every nook and cranny of your card to make very sure that there are no flaws on the card (for this, a 10x lighted jewelers loupe is quite helpful).
Professional graders are usually very tough. If you go in expecting a lot of your cards to obtain "Gem Mint" designation, you might be in for a rude awakening. Some of the grading services now have population reports at their web sites, giving breakdowns showing how many of a certain card received the designations "Gem Mint," "Mint" and so on. If you peruse these population reports, you will discover how few cards receive the "Gem Mint" designation. This should give you some idea of how difficult it is to receive this top grade.
One thing to consider in deciding whether the benefits of grading are worth the costs, is the risk you incur in sending your cards in for grading. In a few reported cases, cards have been damaged in the process between the time the cards are sent off and the time they arrive back. This doesn't occur often, but you should acknowledge the risk (however slight it may be) of this happening, and it is always a good idea to have your cards insured when you send them off for grading. There have also been rumors that some grading companies have replaced submitted cards, with a less desirable copy of the same card.
The recommended way to submit cards is to place your card in a soft sleeve and then to place the sleeved card into a large "Card Saver" or some holder in which the sleeved card cannot move around and be potentially damaged. A top loader should work fine if you tape it tightly at each side on the top so that the top loader will be tight and permit little to no movement of the card.
It should also be noted that while professional grading companies offer the promise of accurate and consistent grading, they are rendering a professional opinion, and opinions can vary from one professional to another, and from one time to another. No company has earned the reputation for being perfectly accurate and consistent, but by and large, you get what they advertise. Before you submit cards for grading, it might be a good idea to examine some that have already been graded, so that you have a better idea as to what a card receiving a specific grade designation typically looks like. This way, you will know whether or not your cards have a good shot at attaining a certain grade designation.
- Who are the major grading companies? Which one should I send my cards to?
The companies that have the strongest reputation nowadays are PSA (Professional Sports Authenticator), SGC (Sportscard Guaranty), and BGS (Beckett Grading Services). There are many other companies, but these are the ones taken most seriously and for which there is most market demand.
Of these three, PSA is the "industry leader" and has been around the longest. There are many more cards submitted to PSA on a regular basis than any of the other grading companies. Cards graded by PSA typically command the highest prices. This may have less to do with the quality of its grading than with its reputation, and it is not guaranteed to remain this way for long. (In fact, recent indications are that BGS-graded cards often command higher prices, particularly on condition-sensitive issues.)
Other than price discrepancies, these companies are generally on par with one another in terms of quality of service and reputation for accurate grading. From what I can tell, none of these is seen as being generally "tougher" in its grading than the others. Preferences for one company or other depend on various factors. Some people prefer PSA for the aforementioned price-advantages. Some prefer the SGC holder the most, but others like the BGS holder with its inner sleeve. (I've found that any of the holders do an adequate job of protecting the cards, and all are, to the best of my knowledge, tamper proof and none have been counterfeited as of yet. It is very rare that any holder will break open unless a significant amount of force is applied to it.) Some people like BGS's 4-point system because it gives them a better idea as to why the card received the grade it did.
I wouldn't recommend one service over the other, so it is basically up to you and how the services cater to your particular preferences. Be careful to read their websites, however, to find out about their grading fees and other requirements for submitting cards, as they differ from company to company.
There are many other grading services out there that I can't even begin to list here, since so many start up and go out of business every month, it seems. (You can find out about some of these by searching through various online auctions.) Besides the three named above, the only ones that seem to stand out among the rest of the bunch are USA (Ultimate Sportscard Authority), and CSA (Certified Sports Authentication). Also, a leading grading authority in Canada is KSA.
- What is the connection to the coin hobby I keep hearing about?
The concept of a third-party "professional" grading service has it's roots in numismatics (coin collecting). Both PSA and SGC are part of much larger grading conglomerates that slab everything from coins to postage stamps, vintage autographs to comic books, even casino chips. In fact, Collectors Universe, the parent company of PSA, is publicly traded on the New York Stock Exchange. Many of its critics fear that grading will bring in speculators looking for the "next big thing" in trendy investment schemes, thereby pricing out the "real" collectors. Just like slabbing did to numismatics in the late 80s/early 90s.