Thanks to Squatting Monk, I also now can add to the Lexicon. :-)
I made changes in the Lexicon for the Get*Name functions. I also added a bit to my code, per below. When I get a few minutes to test, I will see about editing the entries for the other functions.
// TestAssocNames.nss
// print the names of the first PC's animal companion and familiar.
void main()
{
object oPC = GetFirstPC();
string sComp = GetAnimalCompanionName(oPC);
int iCompType = GetAnimalCompanionCreatureType(oPC);
string sFam = GetFamiliarName(oPC);
int iFamType = GetFamiliarCreatureType(oPC);
SendMessageToPC(oPC, GetName(oPC) + "'s animal companion's name is <" + sComp + "> (Type: " + IntToString(iCompType) + ") and his famliar's name is <" + sFam + ">(Type: " + IntToString(iCompType) + ") .");
}