I ran across an interesting article at About.com:Genealogy concerning brick walls. It outlines various steps that one can take to get through those research blocks that we all experience at one time or another.Perhaps the suggestions in the article are not going to be new, but it is also likely that we would all benefit from her review of the basics.
The article suggests that we should first review what we already have in terms of information. For a fact I know this works. By going back and carefully reading military pension files that I have had for some time, I've found additional information that I previously overlooked that was of value in continuing my research. Perhaps we have all done this even with a record as basic as the federal census.
The article also suggests that we go back to the original source for information. The supposition is that there might be additional material that we did not record from that source the first time we visited it.
These are but two of the several suggestions that the article gives. I suggest you check it out at: http://genealogy.about.com/od/basics/a/brick_walls.htm