I am searching for a tire that I do not think is being produced
anymore but I was hoping that I may be able to find four or at least
two of them somewhere.  I have found them mentioned in web pages but
not for sale.  I am looking for a Dunlop SP SPORT 8000 205/55 ZR 91W. 
These tires are made for a 1999 Audi A4 Quattro.  Any information you
could give me would be greatly appreciated.

Dear bavarian84-ga 

Good day!

I could locate the following information from my search attempts. I am
posting it as a comment as I am not sure that it is the exact
information that you are looking for.

The following lnik refers to a company that claims to be the
specialist for the Quattro model:
http://gmg-online.de/index1.html

The following link takes you to their summer tire catalog:
http://gmg-online.de/teile/sommer/index.html

In this section, you will find a pdf file of the catalog (
http://gmg-online.de/teile/sommer/sorei.pdf ). This catalog quotes
Dunlop SP 8000 E 205/55 ZR 91W R16 at 99 Euros (inclusive of VAT).

The orders can be placed using any of the following channels:
Tel/Fax: (0 93 51) 20 60
Mobile: 01 74 8 08 94 40
Email: kontakt@gmg-online.de
Post: gmg - Ihr Autofachpartner
Fahrzeug- und Teilehandel
Inh. Gerald Müller
Bahnhofstr. 23
D-97737 Gemünden

I hope that this is the information that you desire. I leave the
question of considering it as an answer entirely up to you.

Thanks & regards,

reeteshv-ga

I couldn't find the tires anywhere, but I did notice the following article:

http://www.audiworld.com/reviews/wheels/sp8000_01.shtml

It references that the 225/50s may be better (for at least a 98.5).

Look at this link and I believe this is what you are looking for.

http://www.reifen.de/dunlop/sp_sport_8000/205-55_zr16_91w_emfs.html

I can't believe I didn't notice that site is in German.  Sorry about that.