Hey there...

When you say ads do you mean, adsendse or just google posting some of there ads on your blog..???

Sorry to ask, I just want to give you the right answer...

Talk Soon

Tasso Pepi

The question is not clear.
If you wants adsense, apply for the adsense account 1st.

you need first to apply account in the ad site you wanna put in your blog (google adsense,infolinks,adbrite,etc..) then the next thing is just instructed once they approve your application..