I found this using Google Book search:

Other uses of the phrase:
Third World Conflict and International Security: Introduction / Christoph ... - Page 50
by Christoph Bertram, International Institute for Strategic Studies - 1982 -
... the important thing is to get 'US combat boots on the ground' - and to get them there first, so as to place the onus of removing them on the USSR. ...
Assessment of the Plan to Lift the Ban on Homosexuals in the Military ... - Page 123
by United States Congress. House. Committee on Armed Services. Military Forces and Personnel Subcommittee, United States - 1994 -
I am trying to give you a feel of the issue from the boots on the ground, the deck plate level of command, how the effect of the policy is going to be ...
Reserve and Guard Effectiveness: Hearings Before the Military Forces and ... - Page 156
by United States Congress. House. Committee on Armed Services. Military Forces and Personnel Subcommittee - 1993 -
... we will nave identified 85 percent of those personnel, and by the end of the year there will be 2000 boots on the ground doing their job, ma'am. ...
Business Week - Page 31 - 1994
But will it change enough to get boots on the ground? In a similar fashion, Kerry would preserve the Six-Party Talks for dealing with North Korea's nuclear ...
Breaking the Phalanx: A New Design for Landpower in the 21st Century - Page 23
by Douglas A. Macgregor, Center for Strategic and International Studies (Washington, D.C.) - 1997
As America's experience in every major conflict and more recently in Kuwait, Haiti, and Bosnia demonstrates, "boots on the ground" is the only visible tie ...
NATO's Air War for Kosovo: A Strategic and Operational Assessment - Page xxiii
by Benjamin S. Lambeth, United States Air Force, Rand Corporation - 2001 -
... corrective to the unending argument between airmen and land combatants over the relative combat merits of air power versus "boots on the ground. ...
(answered by supergrover)
Sources:
http://books.google.com/books?id=Fn-Sh1nv7pQC&pg=PA37&dq=%22boots+on+the+ground%22&ei=me8AScuiPJK6M_ne7csL
http://books.google.com/books?lr=&as_brr=0&q=%22boots+on+the+ground%22+date%3A1970-1999&btnG=Search+Books