The data is downloadable at http://go.worldbank.org/6HAYAHG8H0 if you or your institution has subscribed.
If you use Stata, you need to transform the WDI data structure into the country-year panel format. P. Wilner Jeanty's ado file WDIRESHAPE may be useful for this purpose.
The List of variables.
The World Bank's region classification puts Djibouti into Middle East & North Africa rather than sub-Saharan Africa. More details on the World Bank's country classification is found here.
For the treatment of countries that broke up, merged, etc., see under the heading of "Country Notes" in the Users Guide.
Data series on tax revenue goes back only to 1990 in the 2005 edition while the data for 1970-1989 was also available in the 2004 edition. This is either because the data before 1990 "have been determined to be questionable" or because "revisions to time-series cause breaks in series which cannot be reconciled by linking or other estimation techniques." See WDI's FAQ.
Data series on general government final consumption expenditure as % of GDP in the 2005 edition seems to be calculated in the current term, not in the constant term. Therefore, change in this series may result from different inflation rates between government consumption goods and the others.