The entrance to the Main Stacks is located on the second floor of the Main Library building. Any UIUC student can go into the stacks as long as you show your iCard at the desk by the entrance and place any bags that you have with you in conveniently located lockers.
If you are unfamiliar with the stacks, be sure to talk to the circulation staff when you go in. They can explain the layout of the stacks and help you find particular books or call number ranges.
For information on the Main Stacks, including maps and policies, and an faq:
The call number for Early Childhood Education is 372.21. Browsing the SSHEL and Main Stacks in this range could help you find sources.
The best way to get detailed secondary source information about some of your educators is to find articles written about them. These articles can give you an idea of what kinds of primary sources are available for your educators, and may also cite relevant secondary sources.
The databases listed below will definitely link you to article abstracts, however, full text of the article may not be available in the database itself. Visit the Help! Do we own my source? tab for instructions on getting access to articles once you know they exist.
To find books about your author, do a keyword search using their names in the Library Catalog. Be sure to type the last name followed by a comma and the first name. For example: Mitchell, Lucy Sprague. If you are having difficulty locating items, try the same search in WorldCat, a catalog listing most of the books held in libraries in the U.S., and then order the book through InterLibrary Loan.
However, many of these individuals may not have entire books devoted to them. Some techniques to find books that talk about your educators briefly are to browse the stacks and check for your educators in the indexes of books that look relevant, and to follow citations from biographical dictionary, encyclopedia, and journal articles about your educator.