I am the manager for a small ISP, and I am wanting to automate certain
parts of our email processing (While still supplying intelligent
customised responses).

I would really appreciate what others think would be the best
approach, and what languages / programs you would recommend to tackle
the issue?

We use:
* IMAP for the team to process email
* A custom written PHP web based customer management program
* A variety of different email programs (MS Outlook, Outlook Express
and Thunderbird) but I could ask them to standardise if this made it
easier.

As I am new to google answers, I am not sure of the way of putting up
the question - this particular one is a multi part question, but I
thought that it would be easier to tackle all together. (and the
answers could depend on the whole solution)? Don't be afraid of the
size of the content either, the actual questions are fairly
straightforward? And tagged with ** (Or I might be out of touch, with
price or expectation so let me know ok?)
--------------------------------------

1A) TAGGING CUSTOMER ID TO INCOMING EMAIL
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
I would like to have a program insert a tag (possibly in the subject
line)  into each email with the customers username: eg:

<1132> Re: My connection

Though I am not sure of inserting hidden tags to the email? 

We have a database that I could get an export of the email addresses
that are on file for each customer, and we could reference against
this or connect to the Customer details SQL database directly.

I had thought that the simplest way to do this would be to forward the
emails through to a (Linux?) server that tags the emails, and then
delivers it on to the mailbox

** Does anyone know of any packages that can do that at the moment?
(Maybe off freshmeat?)

1B) TAGGING A CATEGORY TO INCOMING EMAIL
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
We currently have Thunderbird (the best program I could find that
could sort IMAP) go through our inbox and sort our email into category
folders based on keywords. (Which I tweak to ensure no false
positives)

But as in 1A, I would love to do that on the server, meaning all
messages can be sorted by category, but not have to have lots of
folders Eg:

<ADSL ? PRICE REQUEST> Re: Quick question.

** Does anyone know of a Bayesian program, that allows for multiple
categories? I have only been able to find some that categorise spam
(does Spamassasin do this?)

Ultimately, I would like this categorisation to suggest a probable
template response.

2A) TEMPLATE REPONSE
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
We then want to have a selection of say 40 template answers (eg ADSL
pricing, what to do if dialup disconnections etc.) which humans can
then use to be able to answer most of the incoming questions.

I see 2 ways to handle this, 
A) Signatures
B) A VBS macro or something like that. That inserts the text (also
AutoIT could insert the text from a keyboard shortcut also)

- The only thing that I am finding tricky is that these have
categories (eg ADSL > Sales enquiry) that I need to copy over for
section 3:
 
** If we couldn't categorise the email in question A2, how would we
assign this category over to our ticket system? Remembering that we
use different email programs, and we needed to copy that category over
to the PHP web interface.

3) LOGGING THE EMAIL TO OUR CUSTOMER MANAGEMENT PROGRAM:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
I would like to automatically search for a username and then when
replying to the email, a program opens a ticket in the correct
customer details section, and sets the appropriate category (if we
were able to tag the email as in question 1, this would be easy), and
then copies the details of the email before sending the email.

** What do you think would be the options for doing this?
At the moment, I have been looking at AutoIT, Vbscript or VBA, but was
curious if anyone else had any other ideas?

** Also how would you go about adding a button into say Outlook
Express reply screen that ran some Vbscripts? Eg:

- Lookup customer 
- Template (ideally menu options)
- Send and log the ticket

I am fairly confident I can get the sendkeys working to do all this
part, but how to add a button that then ran that script I wasn't sure
of.

4) AUTOMATION OF CERTAIN ANSWERS
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Finally, if the categories and suggested template work really well,
and we get the Bayesian (or manual rules) working with no false
positives.I would then just auto reply and log the ticket, all
automatically.

I see this as happening only after a long period of testing, to be
sure that the templates that it would be replying with were perfect.

** Last question, if I was to develop an Outlook, or Outlook Express
plugin, how good is www.elance.com for putting up projects like this?
Are there any other sites similar to elance for programmers?