pick up a good c++ book, they'll introduce you to gui programming (or just scan the shelf for a gui programming book in c++)
if you want a good cross-platform library to learn, try wxwidget..
*most* c/c++ compiler should be able to compile standard compliant c++ code..
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lisp hacker

running: FreeBSD 5.4 - still learning

develop with: SBCL + emacs for lisp, Anjuta IDE +gcc for c, SPE for python..
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