Although this site is mostly focused on techniques for advanced students, here is a brief list of the most helpful tips for those new to the study of Japanese.

A few tips to get you started

1. Learn hiragana/katakana as fast as you can. Romaji won't help you learn Japanese. But, don't avoid books just because they use romaji. Of course, kana should be your first choice, but there are plenty of good books that use romaji (since everything used to be done in romaji), so don't ignore them just on the principle they don't have kana. If you can't find a good textbook in your local college bookstore, you can use Amazon Japan:
2. Take a class if at all possible. Lots of people are now trying to study Japanese on their own, without taking a class. For language in general, and difficult languages (like Japanese) in particular, this is really difficult. Language is about talking to people, and unless you have a bunch of Japanese friends, the best practice you're going to get is in a class. So, if at all possible, take a class.
3. Make some Japanese friends. Since language is about communication, you have to have people to communicate with. Anyway, why are you learning Japanese if you don't know anyone who speaks it? Of course it's good to have classmates as friends, but you also want to hang out with as many native speakers as possible. If there are few (friendly) native speakers where you live, use the Internet and make some pen pals (using e-mail). There are a lot of Japanese people looking for English pen pals, so you shouldn't have too much trouble meeting people. You can try Skype too but it's full of perverts.
4. Don't ignore the kanji, but don't worry about learning them all right away. Eventually, if you want to be literate in Japanese, you will need to learn thousands of kanji. But, don't ruin the fun of getting started with Japanese by trying to memorize them all. (In other words, ignore the book Remembering the Kanji and others that suggest you should learn all the kanji first.) You may decide you don't like Japanese; it's better to try out the language first and make sure you want to study it all the way to the fluency level rather than to just start pounding away and not have any fun speaking to people.
5. Try to find a way to live in Japan for at least a few months. Of course this isn't possible for everybody, but if you really want to get good in Japanese, it almost goes without saying you need to go and live in Japan.