I'm trying to create a function in PostGres that'll return

Code:
SELECT l.artist AS aid, l.name, l.lyrics, a.artist FROM lyrics l, artist a WHERE a.id = l.artist AND l.id = $1
Where $1 is the id I insert...However, I can't figure out how to write the function. Currently I have...

Code:
CREATE FUNCTION getsong(text) RETURNS SETOF artist AS $$
    SELECT l.artist AS aid, l.name, l.lyrics, a.artist FROM lyrics l, artist a WHERE a.id = l.artist AND l.id =  $1
$$ LANGUAGE SQL;
I get an error that says the "Final SELECT returns too many columns."

Any ideas on fixing this?