There's a book that I highly recommend called "The Intelligent Investor" by Benjamin Graham. You could very well read that book, nothing else at all, and make good returns for the rest of your life. Nothing spectacular, mind you, but you would do better than most.
Then... fund an account somewhere. I would stay away from straight-up trading services like e-trade. They're just commission houses, and will provide little in the way of profitable funds. Open an account with Schwab, Vanguard, etc. and engage in some of the safe trading that the book recommends to build the core of your investments. Vanguard is, actually, the one I would recommend the most, as they usually have the lowest fees (watch out for "expense ratios" when you buy funds).
I would not recommend buying bonds or equities directly until you have built yourself a model portfolio and tested it for awhile. You can learn by doing with Monopoly money just as easily as you can with real money, and it doesn't actually hurt you if you blow it completely.