You could create GIS maps for a wide range of applications. The one we are most familiar with are the GIS maps used in GPS receivers for driving directions. However, one could create a whole range of maps through the map analysis software such AutoCAD Map, ESRI arcInfo and so on. For example, if you wanted to see, as a school project, how the student population is distributed in the school’s neighborhood, you could create a map like that. You could have the demographic data also superimposed over these location data. That could be how the white, black or the Hispanic population distributed. Beside the general map icons, this kind of mapping would need symbols for white, black or Hispanic households. Thus the kind of icons you need would really depend on the type of mapping project you undertake.
Availability of Icons
Commercially available icons only try to cover the most general needs as the other needs could be really specialized. For example, if you are creating an animal habitat map of coyote population just outside your town area, the need for icons are different and not likely to be in high demand. Such special classes of icons usually are not available widely. Many a times you may need to roll your own symbols/icons for such projects.
What is available is a pack of icons arranged in categories. Typically they sell in the $100 to $250 range. They are royalty free, usually, for distribution. If you needed only 1 or 2 then they will cost you few dollars a piece, $5 being a common number quoted at the top sites. Icons-Land has designed a package that is quite popular. It is being offered by several download sites and are backed by reviews. GIS/GPS/Map Icons usually need to be distinct and kind of jump out of the page so that users can find the type of object of his interest. The icons have to represent different classes of objects, of course. Users would then be able to orient themselves and search and find the points of interest. The icons offered by Icons-Land are available in six groups. Categories they have named as pinpoints, places, containers, GIS, devices and a Misc group. Pinpoints contain symbols used for marking specific places such as objects of various sizes and colors, such as bulbs, flags, needles. Places group contains icons that indicate places such as Hotel, Bank, Hospital, Airport, Gas station etc. Containers group indicate various containers which can be used in GPS tracking applications for cargo and assets tracking. GIS contains icons relates to items used typically in GIS applications such as region selection, coordinate systems, layers, etc. Devices group contains devices that we use, cell phones, PDAs, and so on. Misc would be a group containing all the rest of icons and could be road signs, traffic lights, and so on.
These groupings and the nature of diverse icons availability is similar in other available products. The sizes the icons are available seems to be fairly standard. The sizes typically are 16×16, 24×24, 32×32, 48×48, 64×64, 128×128, 256×256 pixels. Another thing common is the format of these images. The image format is PNG in most cases. Some sites will give you ICO format icons also. Transparency settings are possible.
Selection Criteria & Other sites
Make sure you have the icons you need whatever be the categorization by the producer. Other thing to look for would be if the icons have enough of details that you want to be displayed. The Icons-Land icons look to be well detailed. They are distributed through download3000 and files home. Some of the other similar popular sites are Map Suite and Free Icons Download ().