there is a really really good book out there called:
BORDERS, BINDINGS & EDGES The Art of Finishing Your Quilt
by Sally Collins
this book will teach you sooooo much about borders= finishing techniques- how to make them fit- how to choose the right finishing for your quilts- it is an invaluable resource which i seem to always have within reach!
i highly recommend this book for anyone who makes quilts beyond just copying someones pattern