Downloading Data
The BIGGEST hurdle of any GIS project is obtaining data. Data can be very expensive and more often in various formats, types, projections. Some figures I have heard run the GIS project timeline with 75 % of the time used for data collection & preparation.
Where can I obtain GIS Data?
Because most all information has a geographical location we can display the location within a map. For example, customer addresess can be displayed by address, zipcode, state or other geographic representation. However, simple locating an address without background such as streets, zipcode outlines, ocean, etc needs some orientation. Fortunately, there is a vast supply of GIS data basemap material avaiable. However, free data comes with problems such as projections, scale and even languages.
Where can I obtain Local GIS Data?
GIS data searching (often referfed to as mining) is a big task. The GIS Services provided by the Claremont Libraries is prepared to assist you in your search. However, we have data (geodatabase) for the local area that can be made avaiable to you such as demographic, political, business, crime data and surface layers (dem).
How do I know about the integrity of the data? 
- Remember, Information produced only as good as the data going into the GIS project. For data integrity, you should obtain or develop the metadata. "Metadata" means data about data. The metadata for a geographic information system, like the ingredients for a packaged food, describes the source history and detailed contents of each separate dataset. Several guidelines are in circulation for the categorization of GIS metadata, the most well-known standard originating with the Federal Geographic Data Committee (FGDC) standard. Most GIS managers and users have no time or need to maintain metadata for all the FGDC categories, but most homegrown metadata includes two dozen of them, ideally referenced to the FGDC record numbers.
- Metadata Is very important! Metadata is also complex, initially difficult to read, and initially difficult and time-consuming to produce. Metadata specialists, like librarians, are specially trained to deal with the creation and cataloging of metadata.