I received several responses to this question, but I deleted them :( so I
can't thank you individually...

One person suggested using some of the LIBRARIAN commands in ArcInfo, as
this is essentially how LIBRARIAN works.

Another person suggested using the Automatic Tiled Layouts extension in
conjunction with XTOOLS to create "tiled" shapefiles (for a layout) and then
completing what I wanted to do with XTOOLS.

SOLUTION:
________________________________________________
What I ended up doing requires ArcInfo with GRID. This works, but is kinda
cumbersome. With a few hours of work, someone could do ALL of this in Avenue
much more elegantly...

1) Make a "tile" shapefile. From GRID, set the analysis window and cellsize.
Cellsize should be the dimensions in mapunits of the TILE

GRID: setwindow my_coverage
GRID: setcell 4000
GRID: NumberedGrid = ($$Colmap + 1) * ($$Rowmap + 1)

This will create a grid that is sequentially numbered from left to right,
top to bottom, that is of the same extent and size as your "my_coverage".
This can then be converted to a polygon. Since all cells are unique, you
will end up with a square for each cell in the poly coverage. This can
subsequently be used as the "tile" theme.

GRID: TilePolygons = gridpoly(NumberedGrid)

...then convert to shapefile in AV.

I *think* there's a way to do this in SA... I couldn't seem to get it to
recognize $$Colmap or $$Rowmap.

2) Convert the Tile theme into individual cells to use as clip shapefiles.
So, if your GRID is 10 x 10, you will end up with 100 clip shapefiles. This
is such hoakie way to do this... with some time, this step could be totally
skipped. I wrote a simple little avenue script that will loop through and
write them out, but you have to babysit it and hit "OK" evertime it loops:

--------------------------------------------------
theView = av.GetActiveDoc
themesList = theView.GetActiveThemes

if (themesList.Count = 0) then
  MsgBox.Error("No active themes in view.","Aborting")
  exit
end

theFTheme = themesList.Get(0)
theFTab = theFtheme.GetFtab
theBitmap = theFTab.GetSelection
for each i in 1..224
 strQuery = "[Recno] = "++i.asString
 test = theFTab.Query(strQuery, theBitmap, #VTAB_SELTYPE_NEW)
 theFTab.SetSelection(theBitmap)
 def = av.GetProject.MakeFileName("LM_", "shp")
 def = FileDialog.Put(def, "*.shp", "Convert " + theFtheme.getName)
 anFTab = theFTab.Export(def, Shape, theFTab.GetSelection.Count > 0)
end
--------------------------------------------------

3) Clip the original shapefiles using the clip themes generated in step 2. I
used the batch overlay process in Xtools to do this... worked like a charm.

ORIGINAL QUESTION:
I need to break a large shapefile up into discreet "tiles" of data, and have
an index shapefile of the "tiles."

What I'm envisioning is a script that will take a polygon coverage (it might
look something like a checkerboard), and "clip" an input coverage for each
square in the "checkerboard" - So, one shapefile would end up being "tiled"
into the number of shapefiles in the checkerboard.

Seems like somebody *might* have done something like this ;)

TIA

Chip Hankley