rare book dealers?

[Edith LaForge <OKschlibn@AOL.COM>]

LM-netters:
     I'm ready to sell a set of books passed down in my family since 1855.
 I've checked BPI (at least 20 vols. of it) and don't find a listing.  What I
have is
Sir Walter Scott's _Tales of a Grandfather: Tales from Scotland_  3 vols.
 green and gold binding; many engravings.  c. 1851  publisher A.C. Black of
Edinburgh.
Evidently there are 3 series, 9 vols. in the total set of Tales of a
Grandfather.  I did find a price for the 3 vol set with T of G: Tales from
France.
    Does anyone know of dealers I can send photos to with desciption to get
reasonable price appraisal?  Local rare book dealers tell me I need to know
the price I want before I come to them.  I've never dealt with this situation
and need some helpful hints.   TIA!         Edith LaForge (OkSchLib or
ealaforge)   Tulsa, OK