Here are a few titles that are a little bit on the simpler side:
Precious Remedies Against Satan’s Devices by Thomas Brooks
Brooks shows how Satan opposes Christians and non-Christians.
The Rare Jewel of Christian Contentment by Jeremiah Burroughs
Contentment is rare but precious; Burroughs describes how the Christian can achieve it.
The Bruised Reed by Richard Sibbes
Here is hope for the suffering.
Once you have become accustomed to Puritan writing you may want to try some more difficult works:
Overcoming Sin and Temptation by John Owen
Owen shows you how to do battle with sin.
The Religious Affections by Jonathan Edwards
This is a brilliant work that calls you to love the Lord with your affections.
Resources On The Puritans
A Puritan Theology by Joel Beeke and Mark Jones
This is a massive but very readable work that provides a systematic theology through Puritan writing. The final eight chapters challenge us with how we should be more like the Puritans.
Meet the Puritans by Joel Beeke and Randall Pederson
This book introduces you to the most important Puritan authors and offers brief descriptions of their works.
Puritan Portraits by J.I. Packer
Packer provides short biographies of several Puritan authors.