I've been looking for most of the day so far and can find a plethora of ways to determine if a string is present in an array element but that's not what I'm looking for.

I have a string array that contains authors names, about 175,000 of them.
I have a string that contains (possibly) a book title, series and author name - though not necessarily in that order.

Currently I'm taking the brute force approach (code follows), but there has to be a better way and I'm too involved with the results to see it. Since I'm constantly looking at this array in my code, I'm spending almost 35% of my time in [b]this[b] code so any improvement would be beneficial.

Code:
   Public Function FindAuthors(ByVal file As String) As String
        '   Getting the same name twice (or more?) possibly if the name appears in 
        '   different forms on the same title? -- Fix 1
        If file = "" Then Return ""
        If file.Substring(0, 1) = "*" Then Return file  ' if the author is an "*" then it's a special case possibly no author, or a magazine ...
        Dim loc As Integer
        Dim strTemp As String = CleanInput(file)  ' regex remove all except alphanumeric and white space
        Dim strTempAuthor As String = Nothing
        Dim myOptions As StringComparison = StringComparison.CurrentCultureIgnoreCase
        ' TODO: need to be able to eliminate names which are partials, eve adam <-> steve adams

        Dim strAuthorsOut As String = Nothing
        For Each kvp As KeyValuePair(Of String, Integer) In AuthorSearchDict
             If kvp.Key <> "" Then
                loc = strTemp.IndexOf(kvp.Key)
                If loc > -1 Then
                    strTempAuthor = IIf(cbFNF.Checked, AuthorDict(AuthorSearchDict(kvp.Key)).FNL, AuthorDict(AuthorSearchDict(kvp.Key)).LNF).ToString
                    If strAuthorsOut = Nothing Then
                        strAuthorsOut &= strTempAuthor & "; "
                    ElseIf strAuthorsOut.IndexOf(strTempAuthor, myOptions) = -1 Then      'fix 1
                        strAuthorsOut &= strTempAuthor & "; "
                    End If
                End If
            End If
        Next
        If Len(strAuthorsOut) > 0 Then strAuthorsOut = Microsoft.VisualBasic.Left(strAuthorsOut, Len(strAuthorsOut) - 2)
        Return strAuthorsOut
    End Function
Any ideas short of my continued brute force.