Step 1: Analyze statement (1).
Statement (1) tells us that of the fiction books, there are 6 more that are not written in Spanish than are written in Spanish. Let \( x \) represent the number of fiction books written in Spanish. Then, the number of fiction books not written in Spanish is \( x + 6 \). Since there are 24 fiction books total, we can write the equation:
\[
x + (x + 6) = 24 \quad \implies \quad 2x + 6 = 24 \quad \implies \quad 2x = 18 \quad \implies \quad x = 9
\]
So, there are 9 fiction books written in Spanish.
Step 2: Analyze statement (2).
Statement (2) tells us that of the books written in Spanish, there are 5 more nonfiction books than fiction books. Let \( y \) represent the number of fiction books written in Spanish. Then, the number of nonfiction books written in Spanish is \( y + 5 \). Since there are 23 books written in Spanish, we can write the equation:
\[
y + (y + 5) = 23 \quad \implies \quad 2y + 5 = 23 \quad \implies \quad 2y = 18 \quad \implies \quad y = 9
\]
So, there are 9 fiction books written in Spanish.
Step 3: Combine both statements.
Combining both statements, we find that there are 9 fiction books written in Spanish.
\[
\boxed{9}
\]