Resources related to the act and fact of "communication with God in worship ... [made] possible because the triune God is personal, and has so revealed himself that men and women, made in his image, may address him by name" (New Dictionary of Theology).
Articles & Other Resources

Bible Reading Plans
A wide variety of reading plans -- i.e., the whole Bible in a year; the OT in a year; the NT in a year; NT letters three times in a year; etc. [link]

Personal Daily Prayer Guide
(The title says it all.) (by AC21DOJ)

What is prayer, and what does the Bible teach regarding prayer? What can we learn from the Lord's Prayer? (by AC21DOJ)

Prayer, Submission, and Our New President
What does 1 Timothy 2:1-7 and Romans 13:1-7 teach us regarding praying for and submitting to our government leaders? (by AC21DOJ)

Prayers for America
Excerpts from: Pray for Our Nation: Scriptural Prayers to Revive Our Country (used by permission). (Note: Although written from a somewhat charismatic perspective, this resource is a great place to start in praying for the USA.)

Prayer for the Great Commission Resurgence
A concerted, concentrated effort of the Southern Baptist Convention. [website]

Recommended Resources
(descriptions from CBD)
The Encyclopedia of Prayer and Praise

This book brings together some of the most helpful prayers and teaching about prayer of the past two millennia, offering a vast collection of over 5,000 prayers and writings about prayer. Although it does include hundreds of contemporary prayers, its focus is on the rich and often neglected heritage of classic Christian prayers.

Prayers are organized by theme and occasion, to make it easy to find a particular prayer. There are also indexes of first lines; subjects; and authors and sources. All prayers are addressed to one of the Trinity. Authors range from Abelard and Ambrose through Wesley and Zwingli.

The second part of the Encyclopedia offers over seventy extracts from classic teachings on prayer and praise, as well as prayer collections, stories about prayer and people who prayed, and prayers to be prayed with children.

Prayer: Does It Make Any Difference?

In his most powerful book since What's So Amazing about Grace? and The Jesus I Never Knew, Yancey probes the most fundamental, challenging, perplexing, and deeply rewarding aspect -- the very heartbeat -- of your relationship with God: prayer. In theory, prayer is the essential human act, a priceless point of contact between you and the God of the universe. In practice however, prayer is often frustrating, confusing, and fraught with mystery. Prayer: Does It Make Any Difference? explores the mysterious intersection where you and God meet and relate. Writing as a fellow pilgrim, Yancey explores the questions surrounding prayer that you may wonder about but not know how to express. Above all, Yancey shows you how to pray to a God who sees what lies ahead of you, knows what lies within you, and who invites you into an eternal partnership with Him -- through prayer.

AC21DOJ DISCLAIMER: While Philip Yancey writes about some profound theological concepts, he is not a theologian. In his own words, he writes "as a pilgrim, not an expert." His writing reflects a nonjudgmental, humble willingness to learn from others. His writing style is warm and engaging, and his thorough research results in many beneficial insights. All that said, not everyone will agree with every word he writes.

(descriptions taken from individual websites)

America's National Prayer Committee
We recognize our absolute dependence on God and our desperate need for divine intervention. We believe God is urging us to call all Christians of America to unite in humility and repentance across ethnic and church boundaries to pray persistently for a moral and spiritual awakening in the Body of Christ. We believe this will greatly advance His Kingdom in our nation and worldwide.

Liberty Counsel
Liberty Counsel is a nonprofit litigation, education and policy organization dedicated to advancing religious freedom, the sanctity of human life and the traditional family. Established in 1989, Liberty Counsel is a nationwide organization with offices in Florida, Virginia, and Washington, D.C., and hundreds of affiliate attorneys across the Nation.

The National Day of Prayer is an annual observance held on the first Thursday of May, inviting people of all faiths to pray for the nation. It was created in 1952 by a joint resolution of the United States Congress, and signed into law by President Harry S. Truman. Our Task Force is a privately funded organization whose purpose is to encourage participation on the National Day of Prayer.
(Appears to be an ecumenical website.)
Our vision is tens of thousands of women more closely conformed to the image of Christ through their prayers.

Prayer Planet
Prayer Planet is a global community of believers whom you can join with to pray for issues in Government, News Media, Culture, Faith, and Business.

SBC International Mission Board's PRAYER GUIDES
(FREE prayer guides related to various people groups.)

See You at the Pole
See You at the Pole™ is a student-initiated, student organized, and student-led event. That means this is all about students meeting at their school flagpole to pray -- for their school, friends teachers, government, and their nation. See You at the Pole™ is not a demonstration, political rally, nor a stand for or against anything. See You at the Pole™ is scheduled annually on the fourth Wednesday in September.

U.S. House of Representatives Opening Prayers
From the Office of the Chaplain, U.S. House of Representatives. [link]