Mr. Shulman, author of Anyone Can Make a Million, would no more be without his Arts Newsletter than his Wall Street Journal. But before you write him off as a charlatan or a boob, listen. Though it takes big money to make the big money he made buying art, his advice will guard you against false expectations or taking a loss. He'll steer you away from modern art, and from major European art in general; from limited editions, erotica, and--surprise--the extremely rare (""unless enough people have seen or heard of the product in question, they won't know they want it""). What you should do is specialize--in something relatively small and portable, readily available, trackable in reference books, and difficult to fake (automata watches, on ali counts, for him). The best buys are made following a war or revolution, or at the dispersal of some nabob's belongings; the worst, when an artist or type of art is ""hot."" THAT'S WHEN YOU SHOULD SELL. A calculated approach, then, but not without its rewards--the thrill of the hunt, the pride of possession, the manifold tax benefits, and sometimes, maybe, a real killing.