When a marriage is annulled it's as if it never happened which is why there would be no record of it although, of course, those who attended won't have their memories wiped.
What the heck are you talking about?
An annulment is done through a religious court and proceeds according to Canon Law or whatever form of religious law a particular organised religion governs itself by, and is completely distinct from civil law. You can get a Catholic annulment, maybe a Jewish one, not sure if the Episcopalians or any other organised religions administer annulments. Maybe Islam.
In the RC church an annulment does not mean 'it's as if it never happened'. It means that the conditions for that marriage to be considered valid according to the stipulations of the RC church did not exist. There are several important preconditions to a valid RC marriage, and if one of these is missing the marriage is declared canonically invalid. This does not mean 'the marriage did not exist'.

A divorce is the only form of complete legal separation of parties to a marriage in the US. A civil marriage cannot be annulled. A religious annulment does not equal a divorce.
(The RC church will not proceed with annulment proceedings in the US if a couple has not attained a civil/legal divorce.)
A civil marriage requires the issuance of a marriage licence, an officiant, the couple and in some cases a witness or more than one.
A religious marriage does not require a licence, and other requirements vary according to the religion involved. If the officiating minister fills out certain forms - the marriage licence - and files it with the county court then the religious marriage is also a civil/legal marriage. Religious marriage is not necessary for a marriage to be legal.