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The newest camera / smartphones have GPS chips to geotag pictures so they can be overlaid on maps. For GPS-less cameras:

EXIFtool

GPSbabel

Have a GPS device turned on and logging tracks, take pictures, use the tools to add geotags to pictures.

... or use EXIFtool to strip identifying and geographic information before posting a picture.

I have recently started doing something very similar with my DSLR and a GPS logger. Quick and dirty instructions:

1. Get a digital camera (A camcorder that will export .exif data with JPEG snapshots will work as well) and sync the time with International Atomic Time. If you're not using a camcorder, make sure you have PC sync software to be able to time the shots.

2. Get a fisheye lens or a 360 degree panoramic adapter.

3. Buy a GPS logger. Configure it to track during the same time that you are capturing photo/video.

4. Mount the camera to your vehicle, set up the capture criteria on the capture device (camcorder or digital camera and laptop) and gps logger and drive around to capture your image and geo location data.

5. Download the data and embed the geo-location into your images. I use GPSbabel(GPL Freeware) to convert the data to GPS XML (.gpx) format. I then use GeoSetter(Author's license freeware) to embed the EXIF data and export to Google Earth.

6. You can either export the tracks to Google Earth .kml files, upload to locr.com, or upload the photos to flickr.com and flickr will map them automatically (I use the 3rd option.)

Note: You'll have to use some kind of panoramic converter to be able to view the images in a non-distorted manner. A site dedicated to doing this will all-GPL software is located at http://www.all-in-one.ee/~dersch/

The interface is described in This thread in the Navicache forums. Just pass it the relevant information in the query and you get back an XML file with the data. When it first came out, I had to write a script to parse and import it, but it looks like the current GPSBabel understands the layout of the file natively, if you have space to dump the entire batch into your GPS unit. I grabbed the entire set some time ago, and now just periodically fetch "caches added or updated since" the last time I updated.

As for the GNIS reference data (the USGS-published database of populated places, natural features, radio towers, etc.), they can be downloaded state-by-state from here. For those living or just visiting outside of the US, another US agency also publishes a somewhat less comprehensive but still useful set of location data for various features downloadable from here, and, finally, if you want to play with street map data in the US, the US Census Bureau publishes the "TIGER/Line" data - at least when the census bureau site is accessible...

All of those latter data sources are in the public domain, being publications of the US Government, so they are Legally Free. (Perhaps an odd contrast for a government frequently accused of being bought-and-paid-for by wealthy corporations to the detriment of its citizens - whereas most countries thought of as less at the beck and call of businesses seem to all charge a fortune for this kind of data...) I find them handy for generating my own maps.

• Garmin eTrex. Dirt cheap consumer GPS, pretty rugged, 'smart' tracklog recording and good battery life. There are plenty of accessories available for it: 12v adaptors, bike mounts, RS232 cables, etc.
  If I were buying new, I'd probably go for a Garmin Geko, which is similar but has larger tracklog storage capacity.
• A Keyspan RS232 to USB converter (USA-19 model, but they're probably all the same).
• GPSbabel or MacSimpleGPS for downloading tracks.
• A homebrew Perl script to take the resulting GPX tracks, and draw an Adobe Illustrator 6 file from them.
• Adobe Illustrator. Earlier versions have 'teh snappy' and can be picked up for a few quid, but require Classic. Newer ones suffer from feature bloat and cost loads, but run natively under OS X.

Hardware:
Get a Garmin handheld GPS with a 12v adaptor & download cable, and probably a crate of AA batts.
Stick with consumer stuff. Buying a spare or 3 is cheaper than buying a Trimble survey grade and they all work well enough.

GPS Software:
Download GPStrans &/or GPSbabel.
http://gpstrans.sourceforge.net/
http://www.gpsbabel.org/
You can load the GPS waypoints/track/routes into a mapping format with GRASS GIS's v.in.garmin or gpsbabel+anything.

Mapping software:
Use QGIS. http://qgis.org/
Use GPS plugin.

Data:
Start by downloading SRTM elevation data and VMAP0 digital chart of the world data. Best there will be publicly available for Africa.

Instructions for converting into a usable format here:
http://grass.ibiblio.org/newsletter/GRASSNews_vol3 .pdf

Import and crop with GRASS GIS (r.in.srtm and v.in.ogr modules) and either use with QGIS directly or export into a secondary more popular format for use with other software.

GRASS works well on a Mac. http://grass.ibiblio.org/

GPS interface programs should work on a Mac, GPStrans is command line only so with some hacking and GPSbabel is well maintained so there should be a Mac port by now.

SRTM: http://www2.jpl.nasa.gov/srtm/
VMAP0: http://www.mapability.com/info/vmap0_index.html

According to the FA, the route information is transmitted to the client in some encoded form, then sent back to Google to request a PNG file. If someone could reverse-engineer that encoded form, and if it actually contained usable information, you could probably find someone who'd be willing to write a module for GPSBabel to handle it.

I started implementing Garmin USB support via libusb in GPSBabel a while ago. There's some kind of a problem with the bulk read that I never got past. Any Garmin USB-using libusb jocks are encouraged to contact me so we can get it over the finish line.

You can find the current status on our mailing list archive.

Garmin has gone out of their way to not document the WIRE PROTOCOL of the USB units (60C, 76C, 96C, VistaC, Quest, 26xx, etc.) but to instead document the API into their underachieving Windows driver.

An earlier version of the spec pretended to be a protocol spec. I contacted them with a number of discrepancies betweeen my observations on a protocol analyzer and that specification. Within a few weeks, a new version of the spec appeared that removed the pretense of being a protocol spec.