If you back up your database and logs now (if you have not truncated / truncated them), you can restore this backup to a point in time before you drop the table. See this technology article:
http://technet.microsoft.com/en-us/library/ms179451(v=sql.100).aspx
Just make sure that you are not overwriting the old backup, as if you could not restore it to this point in time, then you may have to use the older one as indicated in other answers.
Also, make sure you restore it to the name of the new database and rename it after you are satisfied with how the data returns to how it should be.
source share