Basicly, if I miss my flight home due to hold ups on my 1000km journey back to the airport in Johannesburg I need insurance sufficient to pay for a replacement flight.

air companyes don't cover personal problems if you miss the flight.. and sincerly l don't know if there's any insurance...

You can buy travel insurance from most major insurance companies. AAA has a good basic plan for under $40 that will cover you (reimburse you) in case you miss your flight, your flight is canceled, you need medical attention, or in case anything should happen to your luggage.

Travel protection insurance is available to cover delays in travel -- but must be purchased before you leave the US (also, you must be a US resident to purchase this coverage from a US-based company).The premium is determined based on the total cost of your trip and will cover missed connections, lost luggage, delays and medical expenses.Many suppliers carry policies, but it's best to read carefully the policy provisions, especially the exclusions to insure you know what the plan covers.Remember, if it looks like you won't make it back to Johannesburg before the return flight departs, to contact the airline and cancel your ticket. Once the plane departs, the ticket will have no value and you will not be able to get a credit toward a new ticket.Have a great trip!