I have a number of bottles of wine, and I am wondering how much they
are worth? 
They are labled Domaine La Turqe Bel-Air, Bordeaux
Superieur - Cotes De Castillon, 1983, G.A.E.C Jean Lavau & Fils.
I've done some simple searches, and found the region and brand, but no
information on whether this is a good vintage, or of any value?

1983 was a very good (a bit short of great) year for Bordeaux, most
notably the lower river area, especially near the village of Margaux,
where the Dordogne and the Garonne meet to form the Gironde. Your
Castillon is from well up the Dordogne and is one of the lesser
appellations but it is more likely to delight than be denture cleaner.
Quality is not uniform in this business, however, so be forewarned.
Usually a claret is best at 6 to 12 years, though the powerful ones
can go quite a bit longer. It is not unheard of to have 30 and 40 year
old outstanding performers.

1982 was a stupendous year and 2000 was nearly as good.

Bordeaux goes with anything even though pompous oenophiles would have
you think it is only for sophisticated meals. Try it with a nice curry
dinner or good Italian food and you'll be amazed.

Hello,
Respectfully, Domaine La Tuque Bel-Air is considered a very mediocre
vintner in its best years.  While 1983 was a good vintage in Bordeaux,
the wine you possess is more than likely past its prime.  As for its
worth, in the very good growing years of 2000 & 2003, DLTBA still
produced inferior wine that sells for $5 - $7 a bottle in Europe
(e.g., Wine Spectator gave the 2003 & 1985 DLTBA an average score of
72 / 100 points -- grocery store wine is typically in the low 80s).  I
can?t imagine anyone paying more than $10 a bottle for the wine, and
only for the novelty of owning a 20+ year-old bottle of Bordeaux.

My recommendation is to open a bottle, decant it, let it breathe for
an hour or two, and taste it for yourself.  If you like, fantastic! 
If you don?t like it, it will still make a great gift to any friend
who collects wine.

Regards,
Plaster

References:
Côtes de Castillon:
http://www.terroir-france.com/region/bordeaux_castillon.htm

Bordeaux vintage chart:
http://www.winespectator.com/Wine/Vintage_Charts/Vintage_Charts_Sub/0,3843,France_Bordeaux_Older%2BVintages,00.html

Map of Bordeaux wine region:
http://www.terroir-france.com/wine/bordeaux_map.htm

Going rate for DLTBA:
http://www.wine-searcher.com/prof/wine-select.lml?ID=LMZTBJ1NNQV00BD

Can you help me understand what you felt was missing from my response
to your question?

markvmd and splaster - thanks for your great answers. The bottles are
at my parents, so the next time I'm down we'll be checking out the
contents of the bottles.

Cheers!