There's not much to say except....
http://www.xtremedotnettalk.com/showthread.php?myVar=92046&myOtherVar=hello
Start your string after the question (?) mark, the first part is the variable name then an equal (=) sign, the second part is the value.
To concat many items together use the ampersand (&).
In your code you would receive the string like this...
dim s1 as string = string.empty
If not request.querystring("myVar") = nothing then
s = request.querystring("myVar")
end if
dim s2 as string = string.empty
If not request.querystring("myOtherVar") = nothing then
s2 = request.querystring("myOtherVar")
end if