Jane's.com is at the moment not accessible, but a recent summary (heavy on al-Quaeda and bin Laden) is worth looking at.
JSTOR has a few items, none very recent:
A Close Look at the Demography of Afghanistan (James Trussell, Eleanor Brown Demography, Vol. 16, No. 1. (Feb., 1979), pp. 137-156)Annie offers 287 records (many duplicated...) with 'afghanistan' in the Subject, many of them GovDocs (hearings and suchlike), and Keyword search gets 252 itemsAfghanistan: Population and Development in the "Land of Insolence" (Samuel S. Lieberman Population and Development Review, Vol. 6, No. 2. (Jun., 1980), pp. 271-298)
Soviet Islam and World Revolution (Martha Brill Olcott World Politics, Vol. 34, No. 4. (Jul., 1982), pp. 487-504)
Internal Battles and External Wars: Politics, Learning, and the Soviet Withdrawal from Afghanistan (Sarah E. Mendelson World Politics, Vol. 45, No. 3. (Apr., 1993), pp. 327-360)
United States. Central Intelligence Agency
Ethnolinguistic groups in Afghanistan
[Washington, D.C.? : Central Intelligence Agency, 1997]
Leyburn-GovDoc-Level 2 PREX 3.10/4:AF 3/10Margolis, Eric S
War at the top of the world : the struggle for Afghanistan, Kashmir, and Tibet / Eric S. Margolis
New York : Routledge, 2000
Leyburn-Level 4 DS371.3 .M37 2000Rashid, Ahmed
Taliban : militant Islam, oil, and fundamentalism in Central Asia / Ahmed Rashid
New Haven : Yale University Press, c2000
Leyburn-Level 4 DS371.2 .R367 2000Grazda, Edward
Afghanistan diary 1992-2000 / photographs and texts by Edward Grazda
New York : PowerHouse Books, 2000
Leyburn-Level 4 DS371.3 .G73 2000Jalali, Ali Ahmad
The other side of the mountain : Mujahideen Tactics in the Sovier-Afghan War / by Ali Ahmad Jalali and Lester W. Grau ; introduction by John E. Rhodes
Quantico, Va. : U.S. Marine Corps, Studies and Analysis Division, [1999?]
Leyburn-GovDoc-Level 2 D 214.13:M 86Cooley, John K., 1927-
Unholy wars : Afghanistan, America and international terrorism / John K. Cooley
London ; Sterling, Va. : Pluto Press, 1999
Leyburn-Level 3 JZ1480.A57 A3 1999Fundamentalism reborn? : Afghanistan and the Taliban / edited by William Maley
New York : New York University Press, 1998
Leyburn-Level 4 DS371.3 .F86 1998Marsden, Peter Richard Valentine
The Taliban : war, religion and the new order in Afghanistan / Peter Marsden
Karachi Lahore Islamabad : Oxford Univ. Press ; London ; New York : Zed Books Ltd., c1998
Leyburn-Level 4 DS371.3 .M37 1998
Google produces 1.3M hits for 'afghanistan'... among the useful:
CIA World Factbook 2000official Web site of the Presidential Palace of the Islamic State of Afghanistan (google cache)
Ethnologue entry for Afghanistan (languages/cultures)
Afghanistan's Web Site ('Afghan-American community')
politicalresources.net array of links
Washington Post Afghanistan page
The Plight of Afghanistan (US State Department)
asiaco.com Afghanistan links
Fact Sheet from US DOE
afghan-network.net (Toronto-based --see their collection of maps and a selection of "Hate Mails & Non-Hate Mails sent to Afghan Network"
18 Sept
Afghanistan data from UNESCAP (UNITED NATIONS
ECONOMIC AND SOCIAL COMMISSION FOR ASIA AND THE PACIFIC)