affiliate marketing = clickbank
adsense = google = adbrite
banner space auctions = leadbolt (ppc)
PPV = novamov (you can set up file share and movie clipembedding) pays $15 CPM
fileshare = megaupload, rapidshare
CPA = content locking
banner ads with PPC or CPM
the list is endless but hope it gives you some ideas
Selecting a niche that you are interested in, learning as much about it as possible, paying minimal hosting and domain costs, and blogging / linking about it, then get advertisements on your website, alternatively xxx affiliate schemes are very lucrative if you are that way inclined and find a willing host.
This really is the most popular way to earn money from your website, it's pretty easier over the others to use as well, even though they can come in very useful which is much better than others which lack the 'money making' idea. However, it's definitely harder for you to make money if you have none to begin with, a lot of people believe that you need money to make money, I personally don't, but it isn't impossible.
Id say that Google Adsense is ofcourse the most popular one. But you need Millions of Daily visitors, to get rich by it. The best chances are, that you make your Website Popular in a special niche, get a nice PR, than try to rent Ad-Spaces | Links.
I have an affiliate site that is just a sub-domain on a US site. I had a very clever Irish-related domain attached to it but they got disconnected along the way. I checked the account last week and found that even though the main domain had been dropped by Google, the sub-domain was still making $1600 a year on its own!
Selling ads to other site owners via BuySellAds is always a guaranteed way to earn money. If your blog is very popular, you could also monetize by selling paid blog posts to site owners who have similar products. You won't want to promote anything not related to your site as this could have a detrimental affect on your search engine ranking.