So I went through the whole Duolingo tree for Portuguese and thought it was high quality and got me good a foundation. As others noted, there is no substitute for actual conversation/interaction with native speakers, and I wish I started that sooner. I also second the recommendation of using something like Anki or Quizlet for vocabulary practice. I only noted that it's good to have a base before starting with professional teachers because if you're budget isn't unlimited, you might not get the bang for your buck having teachers walk you through the most basic stuff like hello/how are you/how much does that cost/etc. that you can get with Duoloingo/Rosetta Stone or similar programs. But if you want to start off with Italki and lessons on day 1 with native speakers, it certainly won't hurt!