A Book of Pagan Prayer by Ceisiwr Serith
This is an awesome little book that inspired me to write prayers of my own, as well as alter a few of the prayers in the book to fit my needs. Part 1 is just About Prayer - with reasons why we do it, ways to make it special, things like that. Part 2 gets into actual prayers. It's divided into sections such as "Prayers for the family" "Prayers for times of day/times of the month/times of the year" "Petitionary Prayers" "Praise Prayers" "Thank you Prayers" and others, so it really covers a wide variety of prayers.
Here is the "Prayer for an Insomniac":
From the deep emptiness of a sleepless night,
my pleas are sent to the gods of sleep.
To the givers of dreams I call,
to those who come in the night, not as dangers,
but as bringers of peace.
Come to me, as I lie alone in the dark.
Slip quietly through the night and place your hands on my brow,
soothing me gently until I slide into sleep.
It really is a wonderful book, with a LOT of different prayers in it. I highly recommend it if you're looking for, well, prayers. It's a great jumping off point to write your own, as well.