Getting the source setup file location

Hi,

I use oneclick deployment for my vb.net application, it install the S/W in "localuser/../...." some random place.
I can get this location using Application.ExecutablePath or Application.startuppath but i find this assembly location not
so good.

Rather using this, i want to use the folder that i used to run the "Install" initially. I can conventionally have this folder in desktop or in C:/ or D:/.
And i can do run update from location. Let say some one download my application from my website and store the download in desktop and run it.

If he again want to run it, he can easily access it from that desktop folder and also all subfolder can be easily maintained here. And apart from that
its easy to update here and remove previous version files whereas in assembly location. their is so many folder created for each update.

All i want to know is how to get this location where the downloaded installer folder is located. When initially i install it, the install page "From" Heading shows
the location of the folder and also i personally know a application that work in this way.

All i need is to keep track of the downloaded folder location and not the assembly folder. Any one how to find "publish source"