Welcome to the forum Dave :)
youll find the members on here are a friendly and helpful bunch :)
have you got any pics?
In my opinion if it's in good condition it's probs worth atleast 2-3k. I say this due to rarity and mileage. The only comparable vehicle would be a late model Audi 80 S2. There's one on eBay currently with the 2.2 engine. The seller is asking £19,999!
I would post the link but it doesn't work for me. Your best bet is putting Audi 80 in an eBay under cars and putting the sorting by price highest first.
Other comparable cars are the rs2 and s2 which are very expensive. But the key to any old performance Audi in terms of its value (not meaning to be insulting there!) is all about the condition, originality i.e. Not modded, service history (ideally full), low mileage and backed up with said service history and colour.
The fact it has no mot will go against it of course.
Oh and if you do get it back on the road we would love to display it on out club stands for up and coming Audi shows! :)
Hope iv helped :)
cheers
steve