Ok, first of all females usually go into heat around 6 months of age. You should wait until she is 2 years old before even considering breeding her though, because in order to be a good mother to her puppies she has to be more than a puppy herself. This will also lessen the risk of complications. This may seem like too long and you might not be the most patient person in the world, but please consider your dogs life before doing something risky.
Now to your other questions. Labs can be sold for anywhere from $100 to the $300 in your case. Champion blood lines can sell for thousands! And no, breeding isn't a great way to make money. It costs a lot to raise the puppies.
Labs tend to have large litters, like between 10 and 15. Your female will be pregnant for 9 weeks, no not 9 months LOL.
Before the puppies are born, you will need to have a whelping box ready so she can have the puppies in it. You may need to help the puppies come out if your female gets too exhausted during labor. It is very stressful on your dog. You will have to monitor mom and the puppies closely to make sure everyone is getting milk and not being squashed by momma dog.
You could sell the puppies at 8 weeks minimum by sticking an add up in the paper or asking family and friends if they would like one. Before breeding you should really set up half or more of the puppies with great homes. Millions of dogs die every day in shelters because of irresponsible breeding and careless owners. :(
Your puppies will most likely be black or mostly black because that is usually the dominant color.
Ok, now by the questions you asked, you know pretty much nothing about puppies. It's great that you have a year and a half to educate and prepare yourself before she's ready to breed. I suggest picking up a Dogs for Dummies book for about 20 bucks. It's a true life saver and has tons of stuff on breeding a caring for the puppies. You really need to know more before getting into such a big adventure! :)
Please take my advice and wait until she is 2, things will go so much smoother. If you did it before then, you could lose mom and/or the puppies, so please think clearly. I would also start a puppy fund so when they arrive it won't be hard on your wallet. Good luck and have fun! :)