Well, if you can believe it, there are just two short weeks (well, 10 days, technically) before Long Beach Marathon. Unless your name is Jamie Brooks, Tim Hickok or Todd Byers, I would NOT sign up for it now. In fact, I would not ever advise signing up for a marathon race day, unless you just didn't get around to mailing in your entry!
Your training should definitely be tapering off now. Please, no more long distance runs. I think you are probably already telling yourself that, anyway. The time for physical preparation is coming to an end, and now you have to get yourself ready mentally. One thing you can do is to visualize the race. If this is your first marathon, I would not recommend sitting somewhere for 5-6 hours, imagining what it would be like to be running that whole time. THAT will not prepare you mentally! I would recommend, however, driving over as much of the course as you can and taking a little photographic memory of your surroundings. I know I always feel a lot better when I recognize where I am. It increases your comfort zone. Besides preparing mentally, you need to slow down and take really good care of yourself. One way to do this, is take your remaining runs easier rather than harder. Try to run them at your marathon pace - I know it FEELS slow, but the one thing you DON'T want to do, is go out too fast, and then crap out early on. Another tack is to make a conscious effort to get more sleep. The most important night of sleep is TWO days before the marathon, and you should have prepared a good base. Finally, watch what you eat. As unexciting as it is, I try and not eat a lot of foods that upset my stomach in the two weeks before my marathon. Again, the most important meal is TWO nights before the marathon. You want to consume plenty of carbohydrates; these will fuel your run, as they are wending their way through your digestive system 24-36 hours later.
So, remember: run easy, get some sleep, and eat well. You're going to do great!