The Basic Stamp 2 is made by Parallax, and you can buy it online from them and pay international shipping, or locally from Microsound.co.za. They will send it overnight counter-to-counter (to your post-office) for R50.

Tom Igoe has a good introduction to the Basic Stamp 2 on his site, including information on programming and trouble-shooting the BS2, and how to do analog and digital input and output with the stamp:
http://www.tigoe.net/pcomp/stamp/index.shtml

Programming applications:

If you're working on a PC, download the Windows programming software from Parallax. If you're working on a Mac running OS X, download the recent OS X Basic Stamp programmer made by Murat Konar.

Parallax BS2 application:
www.parallax.com/html_pages/downloads/software/software_basic_stamp.asp
Murat N Konar's BS2 application:
www.muratnkonar.com/otherstuff/macbs2/

USB-serial adaptors:

If you're working on a desktop PC, you may have a built-in DB9 serial port. If you don't, or you're working on a Mac or a laptop, you'll need a USB to serial adaptor to create a virtual serial port on your computer for programming the Basic Stamp (and for if you'd like the Basic Stamp to communicate with other applications on your computer). There is a wide range of these adaptors to choose from, but only a select few work with the OS X programming application. The EasySync from FTDI is one that's known to work, and is cheaper than the Keyspan, which also works.

Parallax's page for the EasySync FTDI USB to serial Adaptor:
www.parallax.com/detail.asp?product_id=800-00030

Microsound's page for the EasySync FTDI USB to serial Adaptor:
www.microsound.co.za/cart/product_info.php?products_id=390

FTDI's drivers and installation guides for their USB to serial adaptors (Mac and PC):
ftdichip.com/Drivers/FT232-FT245Drivers.htm
ftdichip.com/Documents/InstallGuides.htm

Or make your own USB to serial adaptor...
www.lennard.net.nz/electronics/usbtors232.html

Lunchboxes:

The first thing we do in our classes is to make ourselves an enclosure with power and communication ports for our microcontroller. We wire up the power supply for our stamp and build in separate ports for programming and more general serial communication to other computers. I find it makes trouble-shooting easier if you have a modular system like this. We also make our own serial cables, cheaper than buying them.

The classic pcomp lunchbox - courtesy of Michelle

Wiring the serial ports - left for programming the stamp

Supplying 5v to the board with a 7805 voltage regulator

9v battery as power supply, on and off switch