Reference resources (dictionaries & encyclopedias) are great for getting a quick underst&ing of a topic, developing keywords, & verifying facts.
Using the Subject Headings in the library catalog is a great way to find books on your topic. One way to do this is to do a keyword search, click on an item that looks useful to get to the item record, & then click on the links on the right side of the item record under the "Subjects" heading. Here are some to try:
Costume design
Clothing & dress - History
Clothing & dress - Social Aspects
Costume - History
You can also get more specific:
Clothing & dress - History - 18th Century
Costume - History - 17th Century
Fashion - History - 18th Century
Clothing & dress - History - Pictorial works