recordset trouble

I'm writing a program that runs a sql query, and puts those fields into a long string. Since I am new to .NET ( I'm used to ADODB in VB 6 ), I can't get it to work.
Can someone give me an example on how to run a query and go through the recordset, or dataset, and add it to a string?

ok, I got this far, but I am getting a "Specified Cast Not Valid" Error.

VB Code:

Dim sString(1) As String
Dim dr As OleDbDataReader
Dim iRow As Integer
Dim x As Integer = 0
 
Try
            While dr.Read
                iRow += 1
                If iRow Mod 100 = 0 Then
                    x += 1
                    ReDim Preserve sString(UBound(sString) + 1)
                End If
                sString(x) = String.Concat(sString(x), dr.GetString(0))
            End While
        Catch ex As Exception
            Console.Write(ex.Message)
        End Try

Any suggestions??