Does anyone know any classical songs for the violin?

You don't state your performance level, so I won't recommend a Pagannini Violin Concerto.

You might try violin sonatas by composers such as Beethoven, Schumann, Mozart, Haydn, Bach, Handel, Brahms, etc.

Search on the composer's name to locate the sonatas for free download here:

http://imslp.org/wiki/

There are no songs for the violin. Songs are vocal pieces. There are thousands of pieces for the violin from the 1800s. Almost all composers wrote at least some works for the violin or an ensemble including the violin. You don't say what standard these pieces are to be or whether you have had any recommendations from your teacher.

There is really nothing to go on. Do you need sheet music? Are you asking for pieces to listen to or play?

Bethoven?