In case you haven't heard of tales, check them out. Unique stories set in the SCP universe that don't follow the SCP document format. This means that there are tales told from first person, or have a narrator without needing to pretend that they are some official document an SCP employee typed up. Some of them reference other SCP articles, some are completely separate.
The SCP Wiki is the best place to find an audience who'd be interested in reading an SCP book, so most people who wish to write an SCP book, publish it on the SCP Wiki, usually in parts. Sometimes these multi-part stories are known as series or canons.
Some of them the length of novels. [[New Age - Book I: "Cells"]]
Some are published as lots of small chapters. [[Speed Demon]]
You can also find some original SCP novels on Amazon:
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The S-CORP Incident: a SCP Foundation Book
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The Smiley Coyote Preacher: An SCP-2547 Tale
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Amazon.com: SCP Foundation: Iris Through the Looking Glass (Light Novel) Vol. 1
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Some are available in paperback:
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The S-CORP Incident: a SCP Foundation Book by Christopher Tupa
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The Smiley Coyote Preacher: An SCP-2547 Tale by K.N.S. Latran
But most are ebook only:
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There Is No Antimemetics Division - Kindle edition by qntm
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SCP Series One Field Manual (SCP Field Manuals Book 1)
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