I recommend opening a Roth IRA at one of the big firms, meaning Vanguard, Schwab, or Fidelity. Here's what I recommend buying at each:

• Vanguard - VT - spreads your money around to pretty much every public company in the world; when you get up to $3k invested, you can change to VTWAX and set up automatic investments
• Schwab - SWTSX (US stocks) and SWISX (international stocks) - do 60% SWTSX, 40% SWISX
• Fidelity - FZROX (US stocks) and FZILX (international stocks) - do 60% FZROX and 40% SWISX

Do that until you have a better idea of what you want.