Hey, I'm writing a program that I need to test with 1000s of XML files - any idea where I can get some?
A Google search by filetype yields promising results. Just save a bunch of those pages. A lot of them are RSS feeds.
If you feel up to it, you could write a quick app to scrape the files from Google's search results.
What does your program do?
If you need a particular format, your best bet is probably creating them yourself. You can automate this with a script/simple program.
Actually, creating your own files for testing purposes is likely your best bet in any scenario, since you want to have some control and understanding of your testing inputs in order for the testing to be meaningful.