Create and object like so:
CLLocation *locA = [[CLLocation alloc] initWithLatitude:lat1 longitude:long1];
lat1 / long2 are of type CLLocationDegrees
which is a typedef of a double, representing the point in degrees.
Convert your lat / long to doubles and pass them in, like so:
CLLocation *locA = [[CLLocation alloc] initWithLatitude:[@"" doubleValue] longitude:[@"" doubleValue] ];
The above code was in the example you linked to, you could have very easily google'd the object and it would have brought you to the doc online.
EDIT:
As per Volker's suggestion, if you are getting numbers from a server, there is a possibility of localisation issues, where some local's use a decimal: 46.000
and others use a comma 46,000
.
Something like this would be better:
NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init];
[formatter setLocale:[NSLocale currentLocale]];
NSNumber *temp = [formatter numberFromString:@""];
[temp doubleValue];