Here is an interesting web site that shows you the nearest sightings of a bird species to a given location:
The data is drawn from eBird. To use the site, first drag the yellow dot to your chosen location:
Chose a species and adjust the other settings if you want:
Here are some resulting maps, as of early June 2013.
Note: If you search for certain species, such as warblers, you may get an error. I think the scientific names have changed and the web site hasn’t caught up yet.