Hi ,
I am starting a new online community , it mainly discuss hardware related topics , and i am realy not an advanced developer and mainly all the development made on my website was by the help of friends ....
and right now i need to know alot of information about controling my addz ......

1-Is there a software package or somethiong that can help me manage banners and adwords , so i can just enter the image and link and choose its size and location on the site (instead of using HTML codes)...........Looking through almost every website i found that advertisment system is almost the same , banners with diffrent location and sizes , so i guess may be there is an advances p to mange things like this.

2-If i have a client who is making ads on my site , either by pay-per-click ad or per impression , how to prove my statistics and to keep it clear for both me and them.

3-Is there a contract that should be made before putting ads on my website , or just wait and if he doesnt pay i should stop his ads .

4-How often should i ask a client to pay for his ads , and what is the best method of payment should i use.

Check out phpAdsNew - it's a free ad management system. I don't know of any that primarily deal with bidding and cost-per-click campaigns - most are for banner campaigns, in which case, payment is usually made in advance.

i have downloaded this software and instaled it on the server , and it works great thanks so much , but i still have one question i can't install it on a vbulletin forum.......
is there other ways to make ads on a vbulletin form with similar features as the one you told me about

You can use phpAdsNew and create the campaign on there and then setup your site as a publisher and then you will need to get the invocation code which I use is the remove invocation for javascript. and then you just need to take the javascript code that phpAdsNew gives you and insert it into a template where you want it on your vbulletin installation and you shouldn't have to touch it again. If you want to change the ads all you do is add new advertisor or campaign to that publisher.