I’ve got an excellent resource for you! A website named and consisting of A Collection of Prayers: Christian Prayers, Ancient and Modern.
I’ll quote the final paragraph from the About page here:
The doctrinal standard for A Collection of Prayers is that of the confessions of the Evangelical Lutheran Church. Prayers are not confined to Lutheran sources, however. Some imprecision in doctrinal expression is allowed in some of the more poetic prayers as long as it does not obscure clear Scriptural teaching.
This is a website for nonprofit use, such as education, prayer, and corporate worship. There are roughly 1,200 prayers in the database! AMAZING! And, all these are in public domain.
Browse through the tags. AWESOME!
There is also a page on this website for Books, Online Books, and Other Resources well-worth checking out for collection of prayers available for purchase, a link to Project Canterbury (which I am only newly aware of myself), The Liturgy Archive, Prayer and Verse, as well as a collection of English Collects that seems pretty impressive to me! Plus, you know, recommended reading.
Add it to my growing list of Free Lutheran Resources? Done!
PS. “Wait. Aren’t you missing something? Something obvious?” Yes. Ok. I’m pretty sure the website in this post is a project of WELS Pastor Paul C. Stratman. If it’s a group effort, just let me know! What I do know is that Rev. Stratman must be at least a significant force behind this pretty amazing piece of work! Thank you for your time, energy, discernment, research, and sharing!!! It’s a great idea and a great collection!