Glued on the last piece of my workbench top last night so as soon as I
mount the vises I will be ready to drill the 3/4 dog holes. Question
is how do I do this?

The top is 60x30 made from a 1" butcher block Oak table and two layers
of 3/4 plywood. I didn't weigh it but it is heavy, so heavy I had to
trim the ends with a circular saw because it would have tipped the TS
(good thing I checked it out before I turned on the TS).

The tail vise will be similar to this but it will fit tight on the
corner so that I can clamp either along the front or the end.
http://www.lie-nielsen.com/catalog.php?grp=1297
The part of the tail vise on the end of the bench will be about 12" so
I plan on having a row of holes 1" in from the front and a row ~10" in
running the length of the bench.

My front vise will be about 15" wide and I will put two rows of holes
running front to back in line with that vise.

I doubt I can get the top safely up on the drill press to make these
holes without building a giant contraption so I am going to have to do
it with a hand-held drill.

Will a block of wood with a 3/4 hole be enough of a jig?

Will a 3/4 saw-tooth Forstner bit be able to drill these holes?
(I don't have a 3/4 twist or brad point)

What about a hole-saw?

What should the spacing be?
(I should get at least 10" of travel on the tail vise)