Are there any websites about medieval attitudes about Jews? In google i mostly get websites about a book.

There might be some good information in one of these articles:

http://scholar.google.com/scholar?q=medieval+attitudes+toward+jews&hl=en&btnG=Search&as_sdt=10000000000001&as_sdtp=on

Searching here might get you some good information:
http://www.fordham.edu/halsall/sbook.html

If you need help learning how to search, including how to choose good search terms, go here and scroll down to the links under HOW TO SEARCH THE INTERNET:
http://hanlib.sou.edu/searchtools/

Also ... do you have access to a public library? Even if you go to the library only once to get a library card, you may be able to get the passwords, etc., to access the huge databases most libraries subscribe to these days. You'll often find better information through them than through general searches on the Internet.

Here is an example -- one college's library website (but public libraries usually have many of these, too): (Broken Link Removed)
Click on Electronic Resources/Databases to see the different databases this particular college provides for its students. EBSCOhost, ProQuest, and Facts.com are among the largest and best.

What does your library provide? That's a good place to research.