The rarity of a signature is also important. Here Raab points to Button Gwinnett and William Williams, a couple of obscure men whose signatures are prized as each signed the Declaration of Independence. A Gwinnett autograph may go for $100,000, a comparable Williams for $500. Why such a difference? Gwinnett, who died in a duel at age 42, signed very few documents in his life. It is impossible to complete a signers collection without him, but there may be only 50 such items in existence. Williams, on the other hand, was a town clerk in his hometown for 45 years and signed innumerable items through his long career.

Perhaps the biggest issue for the autograph collector is authenticity. Both fraud and error await the unwary collector. The recent indictment of a Pennsylvania man for selling 400 forged autographs on eBay brought great publicity to the issue, but that is only the tip of the iceberg. Forging an entire book is difficult, so few make such attempts. Forging an autograph takes but seconds, and immediately can create an item of perceived significant value. You really need to read Raab's guide here.

There are many ways to test for authenticity, beyond the obvious one of does it look like other samples of the writer's signature. For example, different types and sizes of paper were used in different eras. A George Washington signature on a paper not introduced until 1800 is phony. The same goes with pens, as usage evolved from quill pens to fountain pens to ballpoints. The color of ink changed. It was generally brown in Washington's time. Blue ink was not introduced until 1850, but a forger unaware of this might forge Washington's name in blue. You should be aware of the inconsistency. As time went on, and important people became overwhelmed with paperwork, a different type of "forgery" arose. There was the stamped and printed signatures, which can look real without careful examination. Presidents and others began using autopens to mimic their signatures. Secretaries would sign on behalf of leaders or stars of stage and screen. Raab has many stories of people offering him signed papers from people who swear they saw the celebrity sign it, even though the signature is not right. Further questioning would reveal that an assistant brought the paper to the celebrity's room for a signature and returned with it a few minutes later. The recipient assumed, but did not actually see the paper signed. The signing, in fact, was done by the assistant.

There are also authentic signatures which are not quite what they appear. In the days when the Winston Churchill you know was a young man, there was a better known, though now forgotten, American named Winston Churchill. You may purchase the latter's signature with no misrepresentation, but still not get what you expected. U.S. Grant's grandson, of the same name, had a signature uncannily similar to that of his grandfather, but you do not want to pay presidential sums to obtain it.

There is much more in this guide, including a wonderful section on autographs of all U.S. presidents from Washington through Reagan. We cannot begin to tell you all that is here, but as an autograph collector, you need to read it. And, we promise, you will enjoy reading it. Here is how to reach the Raab Collection. Call 800-977-8333 or visit their website at www.raabcollection.com.