how to call attend from vb.net form?

Dear All,

I have to work with Telephone Connection with vb.net form. i want call
drop and attend from the form. for this purpose, what control i use in
vb.net form. i trying TAPI controls. but it not worth while.

in internet, more software are there, but no one can interface with
vb.net form.

Can help to me.
any source or links.

thanks to all