Getting VBS to query SQL with variable.

Im having some problems getting vbscript behave like I want it to. The parts I have done, don't even behave as I want (or expected them to.
Below is my script. What I thought would happen, was that it would query the database. and tell me all entires in the users table. However, what it actually does, is it tells me the firstname of the first entry in the table.
However, what I really want, just don't how to do, is to use the SearchFor variable in a WHERE clause, so the userinput would actually be a name, and then the script would search for that name... and give back all the results.

Hope someone can help me out here.

SearchFor = inputbox("Enter persons name")

Set conn = CreateObject("ADODB.Connection")
conn.ConnectionString="Provider=SQLNCLI10.1;Integrated Security=SSPI;Initial Catalog=TestDatabase;Data Source=(local);"
conn.Open
WScript.Echo "Connected"

SQL = "select firstname, lastname from TestDatabase.dbo.members"
Set rs = conn.Execute(SQL)
wscript.Echo rs("firstname")

conn.Close
WScript.Echo "connection closed"


(I'm using MS SQL Server)