Cover Art is a PAIN.
Really, it is. I think most Indie writers will tell you that is one of the toughest things we have to do. We don't have a publishing house to help us with all the little details. We don't have a department in our back pockets to do all the work. Nope, we have to think long and hard about how we want the look of our babies to be portrayed.
Does it have the "feel" of our book?
Does it tell part of the story to grab the reader's attention?
Do the models actually FIT the descriptions in our book? ( OMG, that is such a pet peeve of mine!)
Who does the work you need? There are plenty of places online that offer this service... with a nice price tag to boot. Granted, they do GREAT work and deserve to be paid, but, what about all of us little people who are just starting out? We don't have the funds to put into that. All of our money is going into editing and copy rights.
A wonderful place to check out artists is your local college. Almost all colleges now will offer a computer graphics course. The students there can give you absolutely GREAT work with a much cheaper bill. Especially if you make sure to put their names in the copyright for their work. Their name is put out there, showing off what they can do. That is a plus for them since they can put YOU on their resume once they graduate. That's not a little thing to them, especially if you keep them on retainer.
Whatever you decide to do, just remember to get a receipt or, at the very least, make a copy of the check you give them (with the reason for the check written ON the check). You need this for your taxes. It may not seem like much now, but it will in the long run and no matter who you choose to do your cover art page, it is tax deductible.