Accessing Excel Forms Checkbox

[Adam White]

Here's the code resulting from a macro recording me "manually"
changing the .linkedcell property for an Excel Forms checkbox.

Sheets("EstimatingInput").Shapes(shapeindex).Select
With Selection
.Value = xlOff
.LinkedCell = "C5"
.Display3DShading = False
End With

I want to do this WITHOUT first selecting the object. I tried
"combining" the code like so:
Sheets("EstimatingInput").Shapes(shapeindex).LinkedCell = "C5"
but this does not work.

I'd like to know how to code what I'm trying to do. I'd also like to
know the correct syntax to combine "C" with a numeric variable in the
same statement.

But most of all, I'd like to know where to look to figure this stuff
out myself. I've been trying to use the online help information, and
the Object Viewer ... but since the properties I'm interested in
pertain to Excel Forms objects, they don't seem to show up in the
reference material. At least **I** can't find any reference to
..linkedcell (for example) in there.

I'm spending TONS of time trying to figure this stuff out by trial and
error ... and sure would like to know where to look for the definitive
answers!