I'm 13 years old, home schooled, and by standard definition, a geek. I've spent tons of money on D&D 4e and want to play really badly. Is there anyway I can do this? I see my friends once a week, but have zip time for a long game of D&D, but I live in a pretty large city with two comic shops near me.
Here's some general advice, some of it may not apply well to your situation, but it's food for thought. Since you mentioned you're only 13, it goes without saying that you should make sure your parents are okay with any of these options before you take action.
1) Check out local gaming stores. Often there will postings for groups, or you could ask local regulars / store personnel if they know anybody with a group running. If the store has space to hang out, you could also just spend time there on weekends or after school*, get to know people that way, and then propose getting together to play a game.
* (here I mean "after school" as in after 3-4PM, when most schools have let out, or for whatever schedule you keep with your home schooling.)
2) I know you mentioned that you don't really have time to play when you get together with your friends, but a game session doesn't have to be long to be effective. You could play an hour or two a week. It might be difficult to fit in big battles as they would likely span multiple weeks, but you could focus on small combat encounters and quick exploration until you get a feel for what works.
3) Finally, there are websites where you can join in PbEM/PBF games (play by e-mail/play by forum.) Options include rpggeek.com or roll20.net (if your computer can handle it.) PBEM games would work well if you have a tight schedule because you can log in and post whenever you have time.
Play by E-Mail/Play by Forum
In a Play by E-mail game, all players and the DM communicate through e-mail (usually by sending multiple-recipient e-mails to everyone in the group.) The DM will send out regular updates to explain what's happening, and each player will reply to say what their characters are saying and doing in response. In my experience, these games usually proceed with one or two DM updates per week.
Sometimes the DM might have side conversations with just one or two players, if their characters are off by themselves; that's up to the DM and how he wants to run the game. The games generally move at a slower pace, because the GM needs to wait for everyone to respond with their actions.
Dice rolls can be handled a few different ways. Maybe the DM will take care of all dice rolls and just tell you guys what happened, or maybe he'll ask you to roll and report the results of your checks. It depends on how the DM wants to handle things. Likewise, the DM might post images to show where everyone is in combat, or he might just describe it in text.
Play by Forum is essentially the same thing as PBEM, except that the game is played by posting responses to an online forum, instead of using e-mail. If you follow the link to RPGGeek I included above, it takes you directly to the PBF forums, where you can see a number of games in progress right now. You can browse around to see how games are being played (in a lot of different RPG systems, not just D&D.) There are also some "pinned" topics at the top of the forum, with information for new players.
I'm thirteen as well and have also been homeschooled, and also love dungeons and dragons! I would say you should find somewhere like a community center that you could have the game at, or possibly you or a friends house. Set up a day and time that will work for all of you and see how it goes. You will need to really push your friends to try and work on their character sheets before the first meeting though. We had that problem at my D&D group. And if anyone needs help with it you could always offer help at the next meeting or time you'll see them.