This question comes up quite a bit, so I thought I'd make a sticky answer:
Currently WiGLE uses Census Bureau TIGER data for street-level U.S. maps. We use low-resolution VMAP0 U.S. Military data for the rest of the world. Both data sets are unencumbered by copyright or redistribution restrictions, so we can use the data sets to generate maps without legal entaglements.
The U.S. government has higher-resolution VMAP1 data sets for the rest of the world, but for the most part has not released it. There are groups trying to make that happen. It would be a good thing.
There is an arcview Canadian data set that we may write a parser for.
Other than that we have no street-level data for outside of the United States, so there are no MapPacks or MapTrees for them. If anyone finds or would be willing to donate such data we would very much appreciate it.
Other folks have set up ways to use other maps as backgrounds for JiGLE/DiGLE etc. There is a note on the NetStumbler forums for how to make MapPacks from GPSVisualizer, which takes maps from other random web sources to use. Since WiGLE does not have rights to use any of those maps, we do not package them up.
If you'd like to make your own Raster MapPacks, there are instructions in the wiki.



