There are tons of great resources on the Medieval time period in the West Shore Databases. For this project, I found that eLibrary and Gale Virutal Reference Library worked the best. Keep in mind that you may need to alter your keywords. Try "Middle Ages" or "Dark Ages" as a search term. Put quotes around terms you want to keep together. Don't forget to copy and paste the MLA citation into your Works Cited document.
Another great source for Medieval information is Google Scholar. You want the articles tha list a pdf in the right column. Often you can click the links and read partial or full books online. Depending on the status of the book, you may be able to copy and paste or you may have to take screen shots or notes as you read. Scholar provides citation under the entry. Click the quotation mark to copy/paste them.
Another great source for research quality websites in Web Path Express. Log into Destiny (the library catalog) and click on the left column link for Web Path Express. Enter your search terms. You will need to cite these sources yourself, but you can always use a citation helper.
Did I mention books? Actual, physical, paper books? We have LOTS of books on the Middle Ages. You should check them out.