Here you can find tools to use in your projects. (This is a very selective list).
Twitmaps : create a map from a twitter stream.
Google Fusion : create tables from spreadsheet data. (For arduino: cut and paste from serial port output into google spreadsheet and choose a chart type.)
Leafletjs : create maps -- needs a knowledge of javascript
Google Map Maker : create maps using google maps (there are many map generators available on-line for google maps…)
Arduino : lots of help , examples and discussions
Instructables : tons of step-by-step examples