The very best Elizabethan costume book is Renaissance Faire Costumes by Carolyn Schultz. It is available at the Renaissance Pleasure Faire. This book will give you pattern brands and numbers, shortcuts, and directions. These cover a variety of levels of society, from peasant to royalty.
I keep a closet just for costumes and costume materials. I have a chest full of hats and hangers of old pettycoats. I also have face paint, Body Doodlers™ and makeup. Guess who is Ms. Popular just before Samhain!