A lot of bloggers have tried to make money off of private ads. I have seen great success stories and horrible space that just sits empty. Here are a few tips for selling, and managing your private ads.
Sell through a variety of venues.
Digital Point. For almost everything, Digital Point is a great place. Sure, they are slowly becoming a troll infested hate mongering forum bred society, but eventually all forms degrade to that standard. Hopefully, DP will improve in the future. However, sites with higher PR and selling points can unload some extra advertising space pretty easy, or even commit the Satanic Act of selling links!
There are so many new ideas coming online everyday. Some of the most recent that I have found useful are sites that allow you to sell 125 x 125 ads and other ad formats through an auction system. There are several of these and you can easily find them by searching around. I do not have a real great one to recommend, yet.
Ask friends. I have sold ads for a measly amount of money to some of my friends. It is crazy how little I sold the ads to them for. However, they are my friends. If you are a blogger withouts friends, you have nothing to blog about. Make SOME, oh and BTW thanks to Bree for buying 2 125×125 ads, there is still one available if anyone wants to contact me. Please, please, please do not spam your friends or people you don’t know with ads. It just is not nice
TRADE
Yes, if selling doesn’t work out well for you, try trading. You might be able to get your ad put on another more popular blog, just by trading. There aren’t a ton of bloggers out there willing to do it, me included. Although, I have a good reason behind it. This is a blog about making money, not about personal things. I have to monetize every pixel to its best potential. Just look around Digital Point, some bloggers will trade ad space or links. They usually require reciprocal links. 
GIVE AWAY ADS
Yes, if you really cannot fill that ad space give it AWAY. Create a contest, draw a name out of a hat, have a raffle…woops. Just a small side note, under U.S. law you are technically required to have a raffle license to operate a raffle, online or off. Don’t want anyone getting arrested for holding a contest on their blog. Anyways, only give it away for a maximum of three months, probably one for most blogs. You will hopefully turn your blog into something great in three months and will be able to sell your ad space no problem.
One note; make sure your ads are placed well. Ads placed above the fold and near the top of the fold create the highest sales. Proper blog design helps as well!
On that note, Ad’s will start flying out of here like birds. Hopefully, they do on your blog too.
January 16th, 2008 at 2:47 pm
I think you covered all the basics
January 16th, 2008 at 2:47 pm
sounds like a good idea
January 16th, 2008 at 3:04 pm
@Matt, didn’t you sell a couple ads.
@Jorge, haha sell one to get back at Steve.
January 18th, 2008 at 4:05 am
ya, sounds working, but i’ve never try it before, hehe~
Ryan, u’ve been mentioned this week:
http://bbmarketplace.blogspot.com/2008/01/listening-to-blogosphere-3rd-week.html
January 18th, 2008 at 2:02 pm
Thanks BB, I appreciate it.
January 19th, 2008 at 4:50 am
This digital point is something new to me. Thanks for the sharing, by the way I find that your blog is very interesting too. You got all the points that a successful blogger needed, if you can add in some photo sure it will even be more interesting
keep up the good work
January 19th, 2008 at 3:10 pm
Digital Point is really useful, just don’t get scammed. I will try and add pictures to some more of my posts soon.