Spl1nt3rC3ll

 Thanks! Yes, it was for a school project. 

Gladly! The best materials to use are ammo boxes and containers called "Lock-and-Lock containers. Other common caches are bison tubes and black magnetic nanos. You can camouflage these containers any way you like but some people get creative, disguising them as common, ordinary things. I'm not exactly sure how you can obtain the coordinates without a GPS, but you could try placing them near some kind of landmark and find the coordinates on Google Maps.

I found my first 20 caches without a GPSr, it's actually really easy to do. Just copy the coordinates from the cache page and paste them into Google Maps. Take a screenshot of the area and try to match up the arial view with what you see when you arrive. You could do the same with this map (overlaid with cache locations, I don't know if it's members only though).

You got those two right! There's also TFTF (thanks for the find) and TFTH (thanks for the hunt). Another common one is FTF, which means First To Find. My favorite is Muggle, which is a person who is unaware of geocaching (make sure they don't spot you opening a cache!).
Here is a list of all the terms:
http://www.geocaching.com/about/glossary.aspx#spoiler

Also, if you take something from a cache, replace it with something of equal or greater value. That way there's always something to trade.

A bison tube is a small, cylindrical container with a screw on cap that is attached to a key ring. It's easy to hide by hanging it from objects like branches.

Took me forever to find my first one. I was literally staring at it for the longest time before I saw it.

 Cool, hope you enjoy the hunt! Show me a picture of the cache, if you can. When I first found out about caching, I was amazed to find that some of the caches were in places that I'd walked by every day!

(The images above are pictures of caches I've found, I forgot to mention that in my original post.)