A number of recent books deal with missions, and doing them to really help people. I highly recommend each one of them.

Serving with Eyes Wide Open: Doing Short-Term Missions with Cultural Intelligence
David A. Livermore (Baker Books)

The Poor Will Be Glad: Joining the Revolution to Lift the World out of Poverty
Peter Greer & Phil Smith (Zondervan)

When Helping Hurts: How to Alleviate Poverty Without Hurting the Poor…and yourself
Steve Corbett & Brian Fikkert (Moody Publishers)

Toxic Charity: How Churches and Charities Hurt Those They Help (And How to Reverse it)
Robert D Lupton (HarperOne)

From Dependence to Dignity: How to Alleviate Poverty Through Church-Centered Microfinance
Brian Fikkert & Russell Mask (Zondervan)

Poverty
Jack A. Keller Jr. Editor (United Methodist Women, Inc.)

Travel in Haiti: A true account of Christian missions, orphanages, fraud, food aid, and drug trafficking
Timothy Schwartz