There are lots of free patterns and tutorials for crochet flowers on the internet so I have put a few together in this post that I thought were very cute.
Attic24 has a great tutorial showing step by step how to make a crochet flower.
RoseHip has layered flowers
Scrapbook and Cards shows how to crochet a simple 5 petal flower.
Craftstylish has another tutorial show how to make flowers.
Skip To My Lou shares her crochet pattern.