You are correct that pictures have been taken from outside of the Earth's atmosphere, in space. From space, there are two basic ways in which pictures are taken. The first is from spacecraft, such as the space shuttle or space stations, from which scientists take pictures using cameras and other more sophisticated scientific instruments (Space stations include Russia's MIR and the U.S. Skylab (see
http://www.ksc.nasa.gov/history/skylab/skylab.html ) (which was deactivated and fell into the ocean in 1974) or the upcoming International Space Station. (The Kennedy Space Center web page is probably the best place to look for information on the Space Shuttle ,http://www-pao.ksc.nasa.gov/kscpao/educate/edu.htm ) The pictures are then brought back to Earth to be analyzed.
The other method for taking pictures of the atmosphere from space is through automated spacecraft. Most of the automated instruments that take pictures of the Earth's atmosphere are on satellites that orbit the Earth taking digital pictures. These pictures are stored as information on a computer and transmitted back to Earth where another computer receives them so scientists can study the pictures.
You can find some good pictures from space at NASA's website. Try
http://www.hq.nasa.gov/office/ese/ which talks about NASA's program for viewing the Earth and has a good image gallery. Check out the section for kids too because it has a section on El Nino which is a very important atmospheric phenomenon that scientists have only begun to understand, largely because of taking pictures from space. For more pictures from space, look at the NASA gallery at http://www.nasa.gov/gallery/index.html

A lot of information about the atmosphere is also obtained from the ground or within the atmosphere. Airplanes and weather balloons are particularly useful for studying the atmosphere. What sort of information would you collect about the atmosphere if you had all of these tools available? Why would you collect this information? Look at some of the websites I suggested above to see how scientists use these tools to study the atmosphere and the types of questions they ask and also try the National Oceanic and Atmospheric Administration (NOAA) at http://www.noaa.gov/ which has a lot on studying the atmosphere including the website for the National Weather Service. The weather channel (http://www.weather.com/twc/homepage.twc ) also uses a lot of the information from NOAA satelites and can tell you more about weather. Another website with a lot of good links for information on atmospheric science is http://info.er.usgs.gov/network/science/atmosphere/index.html. You might have to do a lot of searching around here since a lot of the material at these sites is quite technical and even I don't understand it. Good luck!

A good place to start would be a webpage I designed for a class, it can be found at:

http://pollux.geog.ucsb.edu/~jennifer/

It has all sorts of great links to other websites.Check that out and it should be a good
starting point.

NASA has a lot of stuff. You can search from the NASA home page:
http://www.nasa.gov/
Here's something I found a link to from searching there.
http://www.lerc.nasa.gov/WWW/K-12/TRC/laefs/laefs_a.html#2

An excellent place to start a search on the web is from "yahoo.com". Most pictures of the Earth from space were taken by NASA, which is a government agency. You can find them by clicking on "government" on Yahoo's home page. Or you could click on "Science" on the Yahoo home page, and then click on "Astronomy" or "Space". Three good pages I found this way are :
http://ceps.nasm.edu:2020/SSPR.html
http://images.jsc.nasa.gov/
http://www.windows.umich.edu/