Before anything else, I want to mention that choosing language-learning materials obviously depends on which languages you would consider your "base" languages, the languages you can learn a new language through. Of course it makes sense to learn through a native language. Since you're asking in English in an English-language forum, I'll assume that English is a native language for you. If it isn't, then you may have to adjust any advice you get to take this into account.
If English is available as a base language for you, then you're in luck. German has a lot in common with English. This will make the task much easier than it would be for someone learning German through, say, Mandarin or Arabic.
[Disclaimer: There are probably lots of people far more qualified than I am to answer this question. I am currently at about a B1/B2 level in German (CEFR). I learned through four years in high school, about a year in college, and then a year living in Germany. And now I am teaching beginner-level German in China. So, I didn't learn in a very straightforward way or use a lot of different materials.]
The first thing you should decide is what your goals are. Do you just need it for traveling, or do you need to be able to do business? Does "doing business" mean just being able to exchange pleasantries in German before switching into English, or do you need to be able to actually perform a job fully in the language (be "functional")? Do you need to be able to listen to the news, pop music, and watch TV? Do you need to be able to read the newspaper? (Note that I'm intentionally using the word "need" here rather than "want", because I think it's very important at the outset to establish what you want to achieve and then frame that as a need/requirement. "Wants" are often nebulous, shifty, and hard to pin down, so they can erode over time. And telling yourself that you need to reach certain goals will help to prepare your mind for the dedicated effort required to achieve them.)
Setting goals is actually a multi-stage process... In fact, I'm just going to direct you to Olle Linge's excellent article on goal-setting. Don't be distracted that it's on a site about learning Chinese. Every time you see the word "Chinese" just mentally substitute the word "German". The advice holds for anyone setting out to learn any substantial language. Here's the link: http://www.hackingchinese.com/goals-and-motivation-part-1-introduction/
Now that you've set your long-term, short-term, and come up with micro-goals you can use to populate your study schedule, it's time to choose learning materials. I would recommend having at least two or three materials going at any one time. It's important when you get bored with any one source to be able to switch to another one. You should also try to have materials that serve the various parts of the language that you have chosen to focus on at the moment (reading, writing, speaking, listening, pronunciation, vocabulary, grammar). Try to keep reinforcing every of your target skills at least every other day.
And now I'll throw out some concrete recommendations (bearing in mind the disclaimer I made above)...
I recently signed up at http://germanpod101.com to check out their podcast. (There was a deal when I signed up, so I got a premium account for one month for USD$1.) I've listened to about 20 podcasts (mostly at the Absolute Beginner level) and looked at some of the PDFs that come with them. I also downloaded the entire archive of podcasts using iTunes, which they encourage. It seems like a nice, straightforward gentle introduction to the language. It focuses on speaking from the beginning. And I like that it touches on cultural notes and observations in the lessons.
I've also recently been looking at the German learning resources available at Deutsche Welle's website: German Courses | DW.DE
And the Goethe Institute has some free online courses available for various levels. There are currently 26 items at the A1 level: Deutsch für dich
If you're a highly dedicated and studious person, then you can try using the Assimil series, optionally with Prof. Arguelles' "shadowing" method...
As Prof. Arguelles points out, it depends what kind of learner you are. In general, try to get your hands on as many quality materials and expose yourself to as much input as possible. As soon as you get bored with something, switch. Stay interested and motivated. Cultivate your own curiosity around the language. In two words: have fun!
And welcome to the German-speaking world! Herzlich willkommen!
