This question is usually based on the assumption that every family has a coat of arms, that everyone of the name is entitled to bear it, and all that is necessary is to locate it and lay claim to it. This assumption is in the vast majority of cases mistaken. A great many families have never possessed a coat of arms in the historic past, and in some countries families that are not part of the titled nobility, even if they are of aristocratic descent, are forbidden by law to bear arms.
Only a few families are thought to possess arms to which all members are possibly entitled, and they fall into two categories:

[2] The Holy Roman Empire (AD 800 – 1806) incorporated a changing number of states and territories throughout its history, but in broad terms it can be said to have covered Germany, Switzerland, Austria, Bohemia and Moravia, the Netherlands, Belgium, Luxemburg, parts of north-eastern France including the County of Burgundy (or Franche-Comté – the Duchy of Burgundy belonged to France), Lorraine and Alsace, and in earlier times also Denmark and large parts of Italy and of southern France.

South African families laying claim to citizen arms chiefly originate from the Low Countries (the Netherlands and Belgium) and from Germany.

1. Non-aristocratic families originating in the Holy Roman Empire [2] lay claim to the right to citizen arms (bürgerliche Wappen) which are not subject to the strict rules that govern the arms of noble families from their countries of origin.

To the extent that this right exists, and it is subject to considerable legal argument, it is nonetheless preferable to obtain confirmation of ownership of the arms through registration under South Africa’s Heraldry Act (1962) or the obtaining of a grant or registration under comparable legislation in other countries.

No such right exists in any form for families originating in the British Isles, in the medieval Kingdom of France (that is, those parts of present-day France which fell outside the Empire), in Spain, Portugal, Italy or Scandinavia.

Families originating in Greece and Cyprus occasionally have arms, dating back to usage under the Frankish Emperors in Constantinople or the Crusader kings of Cyprus, but most families whose paternal ancestry can be traced to south-eastern Europe have no heraldic tradition to draw on. They are not excluded from devising or otherwise obtaining arms, but there are no ancient precedents, and they must operate in terms of the laws of the countries where they live.

2. Families originating in Poland and the Russian Empire can often lay claim to arms under a system of tribal or clan symbols which was adopted in the late Middle Ages and the early Modern period. However, I have little knowledge of this system and it is of extremely limited application in South Africa.

You might be asking: What about the arms of a family association? The answer is that when a family association registers a coat of arms, it is the property of the association, not of any individual member. Any member of the family may display these arms, but none of them may regard them as his or her own.

Do you have a family crest? and the articles under the heading Family arms: How different devices relate to each other.

* A comprehensive library of illustrations of coats of arms purportedly belonging to South African families can be found at Coats of Arms of South African Families.
CAUTION: It is not an offence to display a coat of arms that is not your property, provided the nature of the display makes it clear that you do not lay claim to it, or that you do not exercise any authority under it.

However, any display that suggests that you are the owner of a coat of arms that does not in fact belong to you, or suggests that you exercise an authority you do not in fact wield, entitles the rightful owner by law to sue for recompense, and to prevent such display.

IT is not possible in law to purchase a coat of arms, either for personal use or for a corporation. A dealer may offer to sell you one, but while he may be entitled to charge you for the print or artwork, he cannot sell you a coat of arms. All you acquire ownership to is to the print or painting, and if you do not own the arms illustrated, this could be of dubious value.

If a dealer claims to be able to provide you with arms that are legally yours, always check his bona fides. In most cases he is not able to do so. Occasionally a dealer might make application to a heraldic authority on your behalf (see next paragraph), but it is usually better to deal directly with such an authority.

The only lawful means of obtaining a coat of arms is through application to a lawfully constituted heraldic authority.

[3] A South African making application to European authorities will need to approach an authority appropriate to his or her own family. Usually these authorities may only make grants to South Africans if their families originated in the country concerned.

The fees entailed in such grants are usually much higher than those charged in Pretoria.

While you will be required to pay fees to acquire arms, this is not regarded as a sale transaction. The certificate received from the authority is not saleable.

In South Africa, the relevant authority is the Bureau of Heraldry in Pretoria.
Other authorities you might possibly want to apply to are the College of Arms in London, Lord Lyon King of Arms in Edinburgh, the Chief Herald of Ireland in Dublin, one of the Spanish Kings of Arms, or one of the heraldische Gemeinschaften that operate in Germany. (See this page for a detailed list.)

Most of these authorities will, under given conditions,[3] be willing to make a grant of arms. The Bureau in Pretoria uses the term registration, but it amounts to the same thing.