Normally getting a decent type in name that gets pure type ins is really tough. And its just too competitive these days with almost all the major type ins already taken.
It is better to identify a high traffic, low competition/high CPC niche area and develop just one site to start with. No point spreading your efforts developing over a 100 domains. Find a high paying niche and get a really good domain name that has your keywords in it. Now, the second part, high paying niches like "available domain names" which have a CPC of almost 25 bucks are hard to penetrate. So you would need to find out what niche keywords are developing or have high traffic. For this you would need tools like wordtracker etc.
Here's an example. Let us take an semi adult keyword like west indian hot babes. Westindianhotbabes.com would be the best domain name. This keyword currently has "NO" competing web page references. And there are around 175-300 people typing it in each day. This is a niche with a wordtracker KEI of almost 45000. There are so many niche areas. Like for example just a few days back the keyword "tamils#x women photos" was being searched for almost 40000 times a day with literally no competition. You have to be real fast these days. I took a niche like tamils women photos and bought the domain tamilswomenphotos.com. This is a good niche too and people type it in. I may develop it later.
After buying your domain you would start focusing on developing it. Spend time submitting it to directories, search engines etc. There are tons of free directories you can submit to. Also some great keywords on your site can rate you higher on SE's. This mantra can surely start getting you good traffic and believe me, just 1 site is enough to make you big bucks. Optimize it with ad networks, affiliate networks, text link ads etc.
It would also be a good idea to slowly build your PR. For this you may have to buy a high PR link for a couple of months. These days a PR7 link costs anything between 60-120 bucks a month. So if you ever reach a stage where your site has a high PR5-7 you can easily make 200-300 bucks a month just by selling text links. Try to add links from good PR .edu or .org sites related to your site topic. Getting a .gov backlink would be precious and really tough.
You can also get good traffic from paid advertising. I am running an adwords campaign for some of my sites and I get nice traffic for really low CPC's. Its worth it.
In a nutshell, focus on 1 domain and you will be rich in a years time.
Patience and hard work + correct research + timely fast action = domain success.
