Where can I purchase a videocassette recording of the 2002 Edinburgh, Scotland
Tattoo?

You can buy a VHS videocassette of the 2002 Edinburgh Military Tattoo
from MusicScotland.com.

Here is the VHS tape in NTSC format (this is the version you'll want
if you are in the US or Canada):

MusicScotland.com
http://www.musicscotland.com/acatalog/MusicScotland_com_Edinburgh_Military_Tattoo_2002_3096.html

And here is the VHS tape in PAL format (this is the version for the UK
and most of the rest of Europe):

MusicScotland.com
http://www.musicscotland.com/acatalog/MusicScotland_com_Edinburgh_Military_Tattoo_2002_3097.html

There is also a music CD available from the same site:

MusicScotland.com
http://www.musicscotland.com/acatalog/MusicScotland_com_Edinburgh_Military_Tattoo_2002_1905.html

My Google search strategy utilized the keywords "2002," "edinburgh,"
"scotland," "tattoo," and "vhs."

I hope this helps you to get the tape you want. If anything I've said
needs explaining, or if a link does not function, please request
clarification before rating my answer, and I'll gladly offer further
assistance.

Best wishes,
pinkfreud