If you're looking for a more civilised way to travel to Hoedspruit (at least a 5 hour car journey), why not consider the Premier Classe sleeper service? I regret to admit that I have yet to do this myself, but I am certainly keen to give this a go!
Whilst not as luxurious as Rovos Rail or the Blue Train, the Premiere Classe service gets extremely good writeups and is a fraction of the cost. As with all rail transport, it makes the journey part of the experience (rather than a hassle) and also saves on the cost of overnight accommodation.
The service is aimed at 'long weekenders' and runs weekly, departing from Johannesburg's Park Station at 17:45 every Thursday, arriving at Hoedspruit at 10:00 the following morning. The return service leaves Hoedspruit at 13:45 on Sunday and arrives back in Johannesburg at 07:55 on Monday morning. The service stops off in Pretoria en route, so I assume that it would be possible for passengers to board/alight at this stop.
The fares include all meals, morning tea or coffee in the departure lounge, afternoon high tea or coffee, accommodation and bedding.
The only downside to this otherwise attractive option is that the service may be subject to delays beyond the control of the operator. Maintenance on the South African railway infrastructure and rolling stock has not been what it should in recent years, and as a result, rail services can be delayed due to factors such as malfunctioning signals, derailments and broken down locomotives. This should not be a particular problem if your itinerary is fairly leisurely, but could be an annoyance if you have a tight schedule.
It is worth noting that Premiere Classe services also operate several times a week between Johannesburg and both Cape Town and Durban. On all routes, there is limited availability, so the service tends to get booked up pretty quickly, especially over peak season, such as public and school holidays.
Update (January 2011): unfortunately this service has been discontinued for the present, but if this really appeals to you, it's worth checking the website below to see if it's been reinstated.
Hoedspruit is a lovely spot, but is not the most readily accessible place from the large urban centres of South Africa, especially if you're going for a short period (such as a weekend). In order to avoid a long car journey from Johannesburg (at least 5 hours each way), we have done quite a lot of experimentation over the years to find a transport solution that is both convenient and cost effective.
First prize is to fly into Hoedspruit itself. This is possible on SA Airlink, but it is usually hellishly expensive and relatively inflexible, with only a few flights a week.
Another obvious option is to fly into Nelspruit (soon to be Mbombela), which looks close on the map. The advantage of Nelspruit is that it is a major regional centre, so there are a fair number of flights (and thus competition) on the route, resulting in greater flexibility and lower costs. However, be warned that the car journey from Nelspruit to Hoedspruit will take you longer than you expect (allow two hours) as the road passes through many built up areas, where speed restrictions and hazards such as pedestrians and livestock will slow down your progress. I would certainly not like to drive this road after dark.
The best option that we have found is to fly with Airlink into Phalaborwa, a mining town on the fringe of the Kruger Park. Although the costs are higher than for the Nelspruit option, they tend to be considerably lower than the cost of flights to Hoedspruit, and there are more flights per week. The drive from Phalaborwa to Hoedspruit thereafter only takes an hour along a good, fast tar road.
I would add that the tiny Phalaborwa airport is a charming and friendly place, with a thatched roof, whimsical wildlife sculptures and animal footprints imprinted onto the cement floor of the terminal building. I always feel as though my holiday has begun when I land there, and in my experience, it's rare that you can describe any airport in such glowing terms!
Any valid drivers licence is accepted provided it is in English, bears a photo of the holder and their signature. A temporary international drivers licence will also do.
A variety of fuel stations are situated along major routes and in all towns countrywide. Most are open 24/7. these stations can be a considerable distance from one another, so fill up before it is too late.
All fuel stations have attendants that will top up the tank, oil, tyres and more. There are no self-service stations in South Africa. A tip is not essential but can be appreciated.