IB Questionbanks, Past Papers, Mark Schemes and Grade Boundaries

Every paper contains sentence "Do not open this examination paper until instructed to do so". Every paper contains words Diploma programme. Almost every paper is PDF file.
So you take search engine and input this query:
"until instructed to do so" diploma programme
(with quotation marks). You can also specify that you want to search for PDF files (not necessary).
Then you find good search engines. Google is the first choice, however it does not find too many papers. You can use Google to find another search engines. Good search engines are Pandia (http://pandia.com), that sends your query to 5 or 6 another engines and sorts the results, msn search (http://search.msn.com) or SOGOsearch (www.sogosearch.com).
When you find a paper, then look at its address. In search engine you usually get only one paper from one site. And when there is one paper, usually there are more somewhere close. So, you take the address of the PDF paper and delete everything, that is behind last slash ('/'). Then you enter it to browser. Now let's take two examples.
a) you find this in search engine:
http://schools.fsusd.k12.ca.us/schools/armijo/Departments/Science/Mitchell/Lectures/paper%202%202000.pdf
So you erase everything behind last / and result enter to browser:
http://schools.fsusd.k12.ca.us/schools/armijo/Departments/Science/Mitchell/Lectures
You will see error message. So you will erase again everything behind last / and enter it again:
http://schools.fsusd.k12.ca.us/schools/armijo/Departments/Science/Mitchell
Now you get a page, where either are links to desired papers (not this case), or link to page, from where you an download the papers (in this example link saying "download physics material").
b) you find in search engine for example this:
http://quilmes.stgeorge.com.ar/material/college/criteria/Examination%20Session2004/ExaminationPack/Group3/English/Economics%20HL%20paper%201.pdf
you delete everything behind last / and enter it to browser. You see then directory listing. In that case it is good to go one or more directory up to see, if there are more papers. So in this case it is directory
http://quilmes.stgeorge.com.ar/material/college/criteria/Examination%20Session2004/
In this case it is also good to browse everything on that server to see, if there are no more papers (on this site you can find also computer science
http://quilmes.stgeorge.com.ar/material/college/IT/papers/
and some more subjects.
c) you find in search engine for example this
http://www.aselley.com/documents/exams/Nov00SLp2.pdf (does not work anymore)
when you try to use previous steps, you find either errors or no link to papers. In this case you can guess names of papers. Here they were for example these:
http://www.aselley.com/documents/exams/Nov00HLp2.pdf
http://www.aselley.com/documents/exams/May01SLp1.pdf
(you change level, paper or session). Sometimes it works (it did here).

Another way of searching for papers is asking other IBers. This way you can get to FTPs and sites, that are not available to public.