As soon as you enter the field of internet marketing, you are taught one thing again and again. Which is it ? Its “Money Is In The List”. They all will tell this to you, from new marketers to advanced level experts. They all know that money is in the list. Some of the top level marketers have lists with prospects in thousands. This is where they make money by doing joint ventures and product launches.
so, whats a list and how to build it effectively? Now thats a million dollar question, because no matter how much you want others to subscribe to your list, its not gonna be easy to begin with.
But once you start to get the hang of it, you would know that its very easy to build lists in particular categories and its even more easy to milk them again and again, provided you offer them valuable information and great products.
Now, to start with , you would need to have account with one of the companies who would be saving all the list data etc. One such company is Aweber.com, they have been in the business for very long and they are the best out there. You can try first month for 1 cent and I bet you won’t be disappointed.
Join them, get your form and put it onto your website. But don’t start expecting miracles 
The key to build a huge list fast is 2 fold. First you need to have targeted traffic (which would be possible via Online advertising). Second you got to give them some free ebook etc , so they are enticed to fill the form and become your subscriber.
One you get them to fill the form and become your subscriber, make sure you offer them valuable information every few days. This would result in retention of most of them. don’t just send an email with crap content. What you need to provide is valuable information. Also its a good idea to slowly build some sort of relation with them and give them the impression that you actually care.
This has always worked for me and will work for as long as lists are being built. Because everyone is looking for information and solution to problems, if you are kind of helping them, they will be your loyal customers.
Then every once in a while, send them an email with the product you are promoting (make sure product is good enough) and not rehashed stuff. You would make plenty of money this way.
Then as time will pass, you would have hundreds of loyal subscribers to make money from.
In the end, I must say, the key is to take action. Go to aweber, get that form and start building that list which would make money for long time to come.