>>>>Check this whole thread Re: Chrtran in .NET Thread #1360482 Message #1360553 - I think it has helpful pointers.
>>>
>>>I can't find anything in there related to Mid().
>>
>>Look for IndexOf of the StringBuilder.
>
>You'll spend an awful long time looking for that :-}

A slow extension method perhaps

public static int IndexOf( this StringBuilder sb, string searchFor)
{
     return sb.ToString().IndexOf(s);
}