First Conditional.

Questions.
http://www.english-4u.de/underl_word_ex1.htm
http://www.english-4u.de/underl_word_ex2.htm

Affirmative.
http://www.perfect-english-grammar.com/first-conditional-exercise-1.html
http://www.englishexercises.org/makeagame/viewgame.asp?id=3226
http://www.learnenglish-online.com/grammar/tests/1stconditional.html

Affirmative and Negative.
http://www.esl-lounge.com/student/grammar/2g24-first-conditional-exercise.php
http://web2.uvcs.uvic.ca/elc/studyzone/330/grammar/1cond2.htm

Song.
http://en.subingles.com/exercises/view/970/Beginner