Couple bits of information to help you resolve the firestations.
- take a look at the spreadsheet online, the coordinates are already there, however they would take some manipulation in excel to get structured right (separate columns for lat and lon)
- instead of doing it in excel, follow the tutorial I posted friday and use the import delimited text file process it does the work for you.
- the key in all of this though is that the coordinates for the fire-stations are based on a different projection system than all of the other city shape files, so we need to setup a couple things in order to get them to play together. If you look at the projection tutorial from ghandi it also explains everything you need to get them to play, short of the actual projection specifications.
- all of the dataportal shapefiles are in nad83 / illinois east which has an epsg identifier of EPSG:26971, the excel coordinates however are in WGS 84 or EPSG:4326. When you get started go to the project settings and do two things, check enable on the fly transformations, and set the project CRS (coordinate reference system) to 26971. Then when you import using the delimited text file you set that incoming data as WGS 84 and the program will handle the rest automagically. FYI, WGS 84 is the most common lat lon representation and used throughout all of the online/web based mapping and gis systems such as google maps.
- once you have it imported you can save things as shape files for future use.
- to get back to autocad or illustrator, just do a save as for the project (not the layer) and youre off to the races!