I would also (as Schotte) recommend you the AudioCD's as studying method; if you want to learn basic german quicklly.
I am big fun of this method (I have also bought for it 140 € Sennheiser headphones with the exceptional attenuation of external noise which is particularly useful for use in a high-noise environment [for example U-Bahn] ) and wish I have started using it from the very begining of my German language learning process. I have visited 2 German courses here in Munchen but nothing improve my German better as self-practice with my MP3 player..
Apart from above mentioned M.Thomas
I would also recommend Pimsleur
It is also good to watch TV/news in German, no matter if you do understand nothing in the beginining.
You can also borrow from bibliotheca some audiobooks in German. Especially those which you have already read in English or kinder books. For example: I was hearing The Little Prince
(by Exupery) AudioBook in German while parallel reading it (in German) to learn the words spelling and from time to time checking English version (to learn the meaning of some uknown German words).
Not a bad idea also; is to hear German songs (lookup the lyrics on internet and translate them) or to rip (into MP3 for example) German Audio from DVD of your favourite film and to hear it several time. With those methods especially you would have fun; forgetting that high-effective studying what you are doing..
I would also recommend you to check LEO
(really super, comlex German-English, English-German dictionary, thesaurus, grammar explanation etc. - you can also hear! pronunciation of most of the German words there ..etc)
I cannot recommend you any learning software. I have tried many but I never realy enjoyed to be stack to my PC/laptop. Nothing beats studying while laying relaxed in the bed with eyes closed or while skating/biking in the sunny day in Olympia Park or snowboarding in mountains etc..
Enjoy & let us known what for have you decided in the end and what helped you the best...
Wishing you success