Yahoo will give you a $100 coupon/credit to start but then they want you to pay a $30 addilitional deposit to start at minimum. Great way to start though with PPC.
Azam: Sign up for Google adwords or Yahoo search marketing, then create ad for your site, add keywords related to your site and set bid for them. thats it! Google adwords charges $5 sign up fee, after sign up you need to add some amount to your account. Yahoo search marketing charges $30 sign up charges but you can get $100 FREE coupon here
be careful though, you want tightly themed campaigns and adgroups. keyword selection and bidding strategy is crucial. if this is your absolute first time, i highly suggest doing some research and reading. my guide project ppc teaches you a lot of useful and effective tactics for ppc. after you understand and have learned some of it, you should start slow. if you have any specific questions, feel free to ask on here, or pm me. dp people are usually nice and willing to lend a hand.
I agree. Do your research and make sure your keywords, ads and landing pages are all tightly related to each other, especially with Google as they will penalize you if they are not.