There are some excellent resources on-line now that are very helpful in looking at specific locations. These can be used to great benefit while looking at locations where ancestors used to reside. Though they were not designed with the genealogist in mind all you have to do is use a little imagination to see how they can be of use to you.
http://Earth.Google.com is one that I use quite often but you must have a very high end computer and a high speed Internet connection to take advantage of the extremely high detailed 3-D views in high resolution. When I am traveling on the road as I am now I only have the use of a good laptop but the graphics capability is not good enough to use Google Earth, so I have found some substitutes.
www.zillow.com is designed for real estate queries and it is evidently linked to the county tax assessors data bases and has real estate valuations posted by address. When you locate an address of interest there is a way to convert from road map view to an extremely high quality aerial photo in 3-D that appears to be from various sources such as satellite imaging and probably low flying aircraft photography, because you can actually view the house or property of interest from four different viewing directions. You can even view both the map and the aerial view side by side if you want. It is powered by Microsoft's Virtual Earth and it is fabulous!
So I keyed in www.virtualearth.com and it took me to www.local.live.com which appears to be the main Virtual Earth search site. The maps and images seem to be the same but they are presented somewhat differently and I did not get the real estate data but it is another way of looking at a same neighborhood or specific address.
When looking at a house that still exists of one of my own colonial era ancestors in White Creek, New York it becomes very apparent why the 1750's Connecticut style center chimney home appears to set back in off the existing road on a long driveway with the front of the house facing the driveway instead of the road. In the time period the house was built it was also used as a tavern for travelers between Saratoga and Bennington, but today seems to be on a low traffic dirt road. When compared to early land ownership maps and this Virtual Earth view it is easy to see that in the olden days the driveway was an actual highway that went past this building, even though the road no longer exists you can make out the tree line and depression of the old road bed.
If you have not yet visited www.NewspaperARCHIVE.com you should. This is a pay site but there are millions and millions of newspapers being scanned and made available for full word or phrase searching. I will be writing a full report on the use and value of this service to genealogists. In my opinion it is one of the "MUST HAVE" best bargains on the Internet.