Just a tip here..
Image hosting is fine for some but, I tried my hand at it as a free industry vetern and found it to be a waste of resources.
If you're going to do it.. make it so they can't hotlink images and get the cheapest 10mbit unmetered server you can find as it will eat alot of bandwidth.
--
Oh and buying one.. almost always a waste of money. Make sure you get stats on unique advertisement impressions and not just unique visitors. If they allow hotlinking there will be alot more 'visitors' than there are people view advertisements.