|your first garb:
Research into Celtic Scottish, Irish, Japanese clothing and a good beginers section Good starting point for the hard to research celtic areas and the beginners section has a good chemise pattern, ideal for italian ren, and also a couple other items.
Some clothing from the middle ages
The Costumers Manifesto
A million and one garb resources including how to articles and documentation.
Elizabethan costuming page
If you are interested in Elizabethan garb this should be your first stop. an excellent resource by a historical costumer laid out in an easy to follow style. This site contains patterns, instructions, research for many diifferent areas in the period, and even information on hats shoes and makeup. Also has much information about Tudor clothing and styles.