facebook help!?

[LolCat]

I'm not exactly sure what you're asking in this question, but it depends on whether you actually deleted the application or if you just removed it from your little left-hand menu on the side.

Removed it from Facebook:
In your search box, type in "Photos" or "Video" and then there will be more tabs, click "Applications". Continue to scroll through the applications (for me the correct Photo application was on the second page). There will be many miscellaneous Photo applications but the one you're looking for will say "Developer: Facebook" and it'll have the Facebook banner on its logo. Click "Add application."

Putting it back on your Applications Tab:
Go to your Applications box on the left, click "Edit". Then there should be a list of applications you've downloaded and beside it a link saying "Edit Settings." Click that, and then it should be the first box that says "Show this on my left-hand menu." Click that, click on your profile or refresh the page and it should be restored.