Compiling a Bibliography
If you cite a source within an essay you will eventually have put in within your bibliography, which is actually much harder to do on the fly then it sounds. Nothing is more frustrating then attempting to compile an incomplete mass of sources into a cohesive biography the night before the essay in question is due. A few tricks can help you avoid this nightmare.
The easiest solution is probably to keep a running tally of your references on the web using an online reference tool such as Mendely, Bibme.org or Refworks. The fact that you can access your saved bibliographies anywhere at anytime makes these tools extremely valuable.
If you prefer to keep a hardcopy of your notes you can collect the references to books and articles on cards of a on 3x5 note cards, On each record the bibliographical details of a single book or article and file those cards in alphabetical order.
If you do lose some of the necessary details for compiling a bibliography (it happens to everyone eventually) the best course of action to take depends on whether the missing information is from a book or article.
If you need the publication data of a book the easiest tool to use is Google Book Search, which stores the publication information of just about every book ever published. If you cannot find the book in question on google book search try the book search engine Worldcat, which serves similar functions. Just be careful you get the right edition of the book in question when using either search engine. If electronic databases do not have the source your looking for you should not hesitate to consult print sources for information.
If you need to obtain information on a journal article, try searching the database it came from in the first place. If you cannot remember where you got the article from in the first place, try using Google Scholar, although this database is extremely incomplete to say the least.
Of course you should always double check any reference information you use, because any electronic database (or human for that matter) can make mistakes.