if she doesn't mind to get married in Shariat court, just go there, ask them what documents do you both need, gather all these documents, bring them to this Sudanian guy in the court, he will give you the date for the marriage contract. On this date bring your american girl and 2 witnesses.... 1 hour – and you married.
Advise your girl to be ready to answer two questions:
1. What amount of money does she want before marriage; 2. What amount of money does she want on divorce.
Done.
Happy married life!