Hi Glen,
I've just been searching around a little, first some info about the car....
The e21 Alpina B6 2.8 was built from 1978 - 1983, and only 533 were built (although some say that some dealers/garages modded the 323i themselves, and gave them the badge B6 2.8... The real ones have been built in Buchloe, Switserland!).
The car has a 2.8 liter engine from the 528i, which normally produces 177 hp, but it was tuned up to 200hp.
In august 1981 the engine received a new air-intake and fuel-intake system, and the power went up to a staggering 220hp! (so you have to check up which one of the engines is in your car, if the car was built after august, it should be the more powerfull engine)
More information about the car is to be found here:
http://www.m5board.com/alpina/e21.htmlBut if you want some information of real alpina owners, you should probably check out this site:
http://www.buchloe-cars.ch/index_2.htmAnd try to mail the webmaster of the site.
I also found a car that was for sale, it was a e21 B6 2.8 1979, and it's been sold for $28.200 (
http://www.motorcities.com/contents/05I80110212036.html)
and this guy on bimmerforums has a b6 2.8 '83:
http://forums.bimmerforums.com/forum/member.php?u=39601That would be all for now

.... Good luck with selling it, and let me know how it went (maybe post some pictures)