diff --git a/stockcli/books.py b/stockcli/books.py
new file mode 100644
--- /dev/null
+++ b/stockcli/books.py
@@ -0,0 +1,120 @@
+import logging
+
+import isbnlib
+from rich.panel import Panel
+from rich.table import Table
+
+from . import utils
+from .console import DEFAULT_PADDING, console, int_prompt, prompt
+from .style import GreenBoldText
+
+
+def add_book_by_barcode(barcode: str) -> None:
+
+    canonical_isbn = isbnlib.canonical(barcode)
+    if not (isbnlib.is_isbn10(canonical_isbn) or isbnlib.is_isbn13(canonical_isbn)):
+        logging.error(f"{barcode} is not a valid ISBN!")
+        error_console.print(f"{barcode} is not a valid ISBN!")
+        return
+
+    userentity = utils.get_request("objects/userentities?query[]=name=books")
+    userentity_id = userentity[0]["id"]
+
+    all_books = utils.get_request(
+        f"objects/userobjects?query[]=userentity_id={userentity_id}"
+    )
+
+    for book in all_books:
+        book_metadata = utils.get_request(
+            f"userfields/userentity-books/{book['id']}", cached=True
+        )
+        if isbnlib.canonical(book_metadata["isbn"]) == canonical_isbn:
+
+            book_metadata = utils.get_request(
+                f"userfields/userentity-books/{book['id']}", cached=False
+            )
+
+            grid = Table.grid(padding=DEFAULT_PADDING)
+            grid.add_column(justify="right", no_wrap=True)
+            grid.add_column(justify="left", style="cyan", no_wrap=True)
+            grid.add_row(GreenBoldText("Title:"), book_metadata["title"])
+            grid.add_row(GreenBoldText("Amount:"), book_metadata["amount"])
+            console.print(
+                Panel(grid, title="[green bold]Book already found[/green bold]")
+            )
+
+            add_to_amount = bool(
+                int_prompt.ask("Add? (Enter 0 to abort)", choices=["0", "1"], default=0)
+            )
+            if not add_to_amount:
+                logging.debug("User aborted task!")
+                return
+            else:
+                book_metadata["amount"] = str(int(book_metadata["amount"]) + 1)
+                response = utils.put_request(
+                    f"userfields/userentity-books/{book['id']}",
+                    book_metadata,
+                    cached=True,
+                )
+                console.print("Successfully updated!")
+                return
+
+    metadata = isbnlib.meta(canonical_isbn, "worldcat")
+
+    grid = Table.grid(padding=DEFAULT_PADDING)
+    grid.add_column(justify="right", no_wrap=True)
+    grid.add_column(justify="left", style="cyan", no_wrap=True)
+    grid.add_row(GreenBoldText("Title:"), metadata["Title"])
+    grid.add_row(GreenBoldText("Author(s)"), ", ".join(metadata["Authors"]))
+    console.print(Panel(grid, title="[green bold]Book Info[/green bold]"))
+
+    ok = bool(
+        int_prompt.ask(
+            "Is the metadata correct? (Enter 0 to abort)", choices=["0", "1"], default=0
+        )
+    )
+    if not ok:
+        logging.debug("User aborted task!")
+        return
+    new_book_id = utils.post_request(
+        "objects/userobjects", {"userentity_id": userentity_id}
+    )["created_object_id"]
+
+    response = utils.put_request(
+        f"userfields/userentity-books/{new_book_id}",
+        {
+            "title": metadata["Title"],
+            "isbn": isbnlib.mask(canonical_isbn),
+            "authors": "\n".join(metadata["Authors"]),
+            "amount": "1",
+            "categories": None,
+        },
+    )
+    console.print("Successfully added!")
+    return
+
+
+def update_isbn(barcode: str) -> None:
+    userentity = utils.get_request("objects/userentities?query[]=name=books")
+    userentity_id = userentity[0]["id"]
+
+    all_books = utils.get_request(
+        f"objects/userobjects?query[]=userentity_id={userentity_id}"
+    )
+
+    for book in all_books:
+        book_metadata = utils.get_request(
+            f"userfields/userentity-books/{book['id']}", cached=False
+        )
+        console.print("Handling")
+        console.print(book_metadata)
+        try:
+            book_metadata["isbn"] = isbnlib.mask(
+                isbnlib.canonical(book_metadata["isbn"])
+            )
+            response = utils.put_request(
+                f"userfields/userentity-books/{book['id']}",
+                book_metadata,
+            )
+        except:
+            continue