Sort of depends on what kind of speed and access you want to
the data.
If you want one of /simple/user editable/, I would recommend you write it
out to a file as a tcl script that sets a dictionary variable.
set loadeddata {
item1 {model toyota color orange}
item2 {model vw color silver}
}
Then you just source the script to load it in.
I use a format like above and write to the file using relative record numbers
in order to keep it up to date.
There are gdbm style databases (
http://wiki.tcl.tk/38656 ) - random access,
on disk.
sqlite ( bundled with Tcl ) - in memory, writes to disk.
More:
http://wiki.tcl.tk/3114