A few lucky people find that alcohol actually IMPROVES their IBS symtpoms. As Lil mentioned, though, in general, most people have problems with alcohol. Beer is pretty much a universal no-no as the carbonation gets people, in addition to the alcohol. Wines are kind of iffy, with most people being able to tolerate hard liquors the best (for whatever reason).
Did you give up all coffee, or only "leaded"? De-caf coffee, I have read, actually still has caffeine in it, although considerably less than regular coffee. That can be a source of problems for caffeine-sensitive people, such as myself. Also, while I find that herbal teas and chocolates are tolerable, regular black tea, like Lipton or Luizianne, are too much. The de-caf versions of them, however, are caffeine free and are tolerable to me.