I just got Fallout 3 for the PC yesterday, and I was happily following the tutorials, but when I clicked on Data Files on the launcher, my .esp didn't show up. When I went to search for it, I found it in a really obscure folder, and it was just a shortcut, and clicking on it just prompted me to find it myself. I probably missed something simple, but Im at a total loss as to what it is. Thanks for any and all help in advance!

http://www.fallout3nexus.com/downloads/file.php?id=640 While it won't necessarily solve your problem, but it is much better than the default Fallout 3 launcher (and doesn't require disc)

Usually when you make a file and it wont show up in esp, its windows UAC acting up. Simply run the geck as administrator at all times to bypass this problem. Right click the desktop shortcut, click Properties, then compatability, and check Always Run as Administrator. Then click OK. Then open the geck (if it was already open, close and reopen it) and load your mod, then save your mod. It should now show up.

Or install the game somewhere besides C:/Program Files. That's probably the easiest way as you'll need to go through those administrator steps quite often if the game is in it's default install path. Creating a C:/Games folder and putting it in there is a good idea since other games can run into this problem as well with the UAC system.

Easiest way? It takes 5-10 seconds for each program that has to do with Fo3 (Geck, nifskope, FOMM, and maybe Fo3edit, so 20-40 seconds) and its a one time thing. I recommend this, but in the future you probably should install things elsewhere to start, as from scratch that will be the fastest way.

Thanks guys, I did the administrator solution, totally worked out and Ill be sure to bring further questions here, extreme helpfulness.