Habelt sends catalogues in printed form or as e-mail and has them on his site. Prices are normally quite okay. . Catalogues by e-mail or on their homepage. Paperbacks are often extremly cheap. You can check their stock on their homepage or at Bibliofind.
Prices are appropriate.
Catalogues are sent by post, but you can check their stock at ABEBooks. Particularly older French books on archaeology can be obtained from Picard. There are often excellent bargains. But you can check their stock as well on their page or on Bibliofind. Smitskamp specialises in oriental studies, but has catalagues on Classics from time to time.