Excellent question. Many different sites offer rules and basic tutorials for beginners, but I'm going to send you to two sites in particular that you're going to find handy even after learning the rules. They are the American Go Association (AGA) and Kiseido. Both offer good starting pages for the extreme beginner.

There are two basic ways to play Go. The first is to physically play the game with a real board and stones. To do this, you need to find a board, stones and someone to play you. Probably the best way to find those three things is to go to a Go club meeting. Where are these Go clubs, you ask? Go again to AGA's website and click on where to play. You'll find a list of all the AGA chapters and other Go clubs in the US, along with an e-mail address or phone number to contact someone from the club. After you find a club in your general area on that list, you can use the contact methods given to find out where and when the club normally meets. Just go and prepare to have a good time.

The other way is to play Go over the internet. Some sites that aren't primarily Go sites still offer the ability to play Go. One of these is Yahoo! Games. Go on Yahoo suffers from the lack of the proper rating system and also some problems with the Java applet screwing up. For the positives, Yahoo is a haven for beginners not yet ready to play seriously on other servers, a good place for groups to meet and talk over a game, and it does not require the downloading of a special client - a Java applet simply pops up.

After you've gathered a bit of experience, you can move on to a dedicated Go server. The most popular of these is IGS, the original Internet Go Server. There are Java applets for IGS, but to get the most out of it, you'll want to download a client. Further information is available at the link above. The positives of IGS is that there are always a lot of players on of various strengths from all over the world. The atmosphere is fairly competitive, which may be a positive or a negative depending on the person. The strength of the players can also be a positive or a negative, as beginners may have a hard time finding opponents of their own strength. Beware those that underrate themselves and those that escape a match.

Other popular dedicated Go servers are Kiseido Go Server (KGS) and No Name Go Server (NNGS). While not as popular as IGS, the people who go to these two tend to like their more friendly, closer community. I don't use these myself so I'm not too familiar with them, but feel free to try them out yourself.

Experience is very important in improving at Go. Play as many games as you possibly can. However, afterwards, you should look over your game to see what your mistakes were, so you don't keep repeating them and reinforcing bad habits. Of course, it's hard for a beginner to see their mistakes at first, so they should look to stronger players for help in reviewing their games. If you don't have a local Go club with people to help you, you can try the Go Teaching Ladder (GTL). There, after you make or obtain a record of your game in .SGF format, you can send it in to have it reviewed by a stronger player. More details can be found at the site itself.

Besides simply playing games, it's also beneficial for the beginner to read up on basic strategy. Rafael's Go Page is one of many sites that can help with this, although it may be found too confusing for some beginners. Another, interactive way to study strategy and help you improve is to go to the Beginner Study Section at Sensei's Library. Not only are the pages at Sensei's highly informative, but you can edit the pages yourself to ask your own questions and answer the questions of others. The people at Sensei's are very nice and it's a fun site to visit for any Go player looking to learn more about the game, certain terminology, and a little history.

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It's important to keep in mind that you won't necessarily progress in Go as fast as Hikaru has in the manga. No matter how long it takes you to reach a certain point however, it's important to have fun along the way. Playing Go isn't necessarily about becoming the strongest player to ever live, but about the enjoyment that comes from playing a game you love.