Land aquisition in Southern Sudan is a less-than-straightforward affair in Southern Sudan. One of the civil war's many impacts is certainly in the way land is treated, both in a transactional and possessive sense. In short, land ownership and transferral is a mix of old and new, clear and opaque, and local vs. state issues.
There is currently an effort to produce a Land Act from the Southern Assembly, but the process is moving very slowly and the bill may not meet the expectations of all parties (e.g. the government policy makers and the land holders/occupants). We hope to see some movement on the bill in early 2009, but that is still up in the air.
A few rules of thumb I've witnessed is that the closer the land is to an urban area, the more involved the acquisition process is. The more the government is involved (I meant GOSS), the harder the process will be. Individual communities are the occupants of the land and have the most say in its use/disposal. Unoccupied land isn't always unused land; South Sudan's pastoralist and farming cultures hold and utilize lands at different times of year and in different environmental circumstances. You cannot acquire land from a distance, you will have to be there, on site, to negotiate. Final tidbit: get someone who knows the terrain and has experience before embarking on a large land acquisition. It will save time, money and your reputation in dealing with the communities in which you desire to enter.
Finally, a great volume of patience is necessary. Most communities and individuals do not have the experience of having conducted a long term lease transaction or outright sale of land. They often believe their land is much more valuable than outsiders would believe. Negotiation is critical as is dialogue and clarity. Most will not sell or lease land without intimate knowledge of the project you want to use the land for.