Have you tried The Commons on Flickr?

Also check the NASA site for space walk.

ChrisL

The Library of Congress have tons of pictures on flickr this is the search result for World War 2.
Now the cool thing about their flickr images is that they all have a description that ends with something called "Persistent URL" if you click that it'll take you to their website where you can click the thumbnail to get a page like this. In this example it's a photograph of a tank and you have access to a 191 Megabytes TIFF.
Most of the images they put on flickr don't have restrictions on reproduction and publication.

Damn you johnnydib... just like that your give away the secret stash!! ;-P

And HERE is one man's attempt to work these ancient scenes into contemporary design.

Thanks everyone!

So...I found:
Picture of I world war
Picture of II world war
Picture of first men on the moon

Not found yet
Picture of first television (here can be a picture of TV from the beginning of broadcast)
Picture of 9/11

Thanks in advance
António

http://commons.wikimedia.org/wiki/Category:9/11
http://commons.wikimedia.org/wiki/Category:Television

Library of Congress photos are public domain, as are all government owned photos that aren't classified.

@DanGayle... that isn't necessarily 100% true.

http://www.loc.gov/rr/print/195_copr.html

They are saying that, to the best of the LoC's knowledge, probably all are OK to use, but that the responsnibility (as always) is on the person who uses the image to accept responsibility for any repercussions (and that the LoC doesn't provide any protection or guarantees, other than presenting what information it has about a particular image). At least that's how I read it.

It is still use at your own risk, even if that risk is only 0.00001%.