Hi, It will take some effort to hammer that in shape. If it is a grid (rather than points) you need to know the columns and rows, and you can add that as a header - the spec is here: http://en.wikipedia.org/wiki/Esri_grid
Next step is to fix the numbers so that the figures are per rows/columns. If the grid has e.g. 200 columns, then 200 figures should be on the first row etc.
You may be able to do that in Access or Excel, but it wouldn't be too hard to prepare a python script too that reformats the file.
A different approach would be to format this to a text file with points (e.g. csv or even excel/access). Then you need to know the coords for each grid cell and calculate that in a separate column for the output: x,y,value - in ArcGIS you would then bring in the table, and use the built in tools to create points, which you then can convert to a grid. Also doable in Access or Excel.