hxxp://yahoo.com
go to the bottom of the page
click "advertise with us"
Read the descriptions and determine if you should click publisher netwwork or search marketing.
Hint: the initials are s.e.a.r.c.h. m.a.r.k.e.t.i.n.g.
Use a little common sense, or at least TRY to find the answer yourself...
And so that you don't have create another thread...
Microsoft's service is called MSN AdCenter
And to save yet another new thread...
Google Adsense and Yahoo Publisher Network are contextual advertising that you can put on your site to make money.