I'm posting this in response to an email request for some sample ASP code to encrypt/decrypt using the DBA Toolkit.  Unfortunately it's been quite a while since I used good old ASP (sans .NET), so I'll post a short ASP.NET/VB.NET snippet that shouldn't be too difficult to translate backwards.  The key items to consider here are that:

1) the UDF's accept and return VARBINARY values, which in .NET are BYTE() arrays.  Hence all the System.Text.Encoding... calls. 

2) The example assumes a few things - that your server is (local), the login is Windows Integrated security, and the default Local Key and Master Key created by the INSTALL.SQL script are still around.

Hope this helps!

Dim Plaintext As String = "This is some Plain Text"

Dim Bits As Integer = 256

Dim Key As String = "Local Key 1"

Dim sqlcon As System.Data.SqlClient.SqlConnection

Dim sqlcmd As System.Data.SqlClient.SqlCommand

Dim sqlcmd2 As System.Data.SqlClient.SqlCommand

Try

    Console.Writeline (Plaintext)

    sqlcon = New System.Data.SqlClient.SqlConnection("server=(local);initial catalog=master;integrated security=sspi;")

    sqlcon.Open()

    sqlcmd = New System.Data.SqlClient.SqlCommand("SELECT dbo.fn_encrypt_aes(CAST(@plaintext AS VARBINARY), @key, NULL, @bits)", sqlcon)

    sqlcmd.Parameters.Add("@plaintext", SqlDbType.VarBinary, 1000).Value = System.Text.Encoding.ASCII.GetBytes(Plaintext)

    sqlcmd.Parameters.Add("@key", SqlDbType.VarChar, 64).Value = Key

    sqlcmd.Parameters.Add("@bits", SqlDbType.Int).Value = Bits

    Dim Encryptedtext As Byte() = sqlcmd.ExecuteScalar()

    Console.Writeline (System.Text.Encoding.ASCII.GetString(Encryptedtext))

    sqlcmd2 = New System.Data.SqlClient.SqlCommand("SELECT dbo.fn_decrypt_aes(@enctext, @key, NULL, @bits)", sqlcon)

    sqlcmd2.Parameters.Add("@enctext", SqlDbType.VarBinary, 1000).Value = Encryptedtext

    sqlcmd2.Parameters.Add("@key", SqlDbType.VarChar, 64).Value = Key

    sqlcmd2.Parameters.Add("@bits", SqlDbType.Int).Value = Bits

                         = "g" convert the relevantou e the article or the Toolkit.chm file for directions)If there were some way wDim Decryptedtext As String = System.Text.Encoding.ASCII.GetString(sqlcmd2.ExecuteScalar())

    Console.Writeline (Decryptedtext)

Catch ex As Exception

    MessageBox.Show(String.Format("Error Occurred: {0}", ex.Message))

Finally

    If Not (sqlcmd2 Is Nothing) Then

        sqlcmd2.Dispose()

    End If

    If Not (sqlcmd Is Nothing) Then

        sqlcmd.Dispose()

    End If

    If Not (sqlcon Is Nothing) Then

        sqlcon.Dispose()

    End If

End Try