There are lots of sites with good patterns, many of which are free. You might have to join to access the patterns, but it doesn't cost anything and is simple to do.
For chemo caps: www.headhuggers.org
For crochet instructions: learntocrochet.lionbrand.com/
For knitting instructions: learntoknit.lionbrand.com/
For knitting instructions with video: www.knittinghelp.com/
For all things knit & crochet: www.interweave.com
Knit and crochet forum: www.KnittingParadise.com
Knitting & crocheting in Middle TN: http://knitandcrochettn.com