boards are 3/4 stock cut to rough length. I need to know if anyone has
a good technique for laminating stock this thick, I need to get a
blank 3" thick. What amount of pressure is needed?

I don't think any great amount of pressure is needed - it's more
important to get all the boards as flat as possible (or cut into
exactly complimentary hills/valleys, I suppose, but that'd probably be
a lot harder than getting them all flat). Do you have a jointer? Or
some hand planes and patience? If not, you might look into renting or
borrowing time on someone else's jointer. If you bought the cherry at
a real hardwood dealer, they might do it for you for a small fee.
As far as laminating technique, you just get the boards flat, glue
them together (any kind of glue will work, TBIII or epoxy would be
best for water resistance), and clamp them. Use clamping cauls (DAGS)
if you don't have enough clamps, or if you don't have clamps that
reach deep enough.
Good luck,
Andy