That map is likely just a matrix or terrain in darkbasic pro. If your looking to create something as simple as that, you can easily create one in dbpro from a heightmap, which is a black and white image that dictates the relative position, in height, of the verticies of a terrain. White represents the highest points whilst black is the lowest. Then a simple tileable texture can be applied and voila.
I sugest you ask about matrixes/terrains in the newcomers section of the forum for detailed advice on the code you would need.
On the other hand, if you mean to create buildings and features of a level, then you can use any modelling package of your choice, more or less, to get decent results. ALternatively, if your willing to fork out £40 then you could get your self 3d world studio from this very website which is specifically intended for levels and such, and has a host of export options including .dbo. I would reccomend the latter, if you have the money. There we
go, arent I nice!
Male modelling isn't just for gays! In fact, if 3DS Max was free, everyone would do it.