I don't have the money for expensive studio lighting (yet) how can I get pro photos?

What can I do to take professional food/indoor photography? My camera is a Nikon D3000 with the standard kit lens [18-55mm]

I have a large window and table top. However as Winter approaches getting the sun to cooperate has become difficult.

My focus is on shooting for stock photography. I eventually want to upgrade but of course I have to start shooting and earning.

Good luck earning very much from stock photography as the stock world has been turned on its ear. That said, if you think of the sun as your first light, then use a couple of simple white cards to reflect the sun's light, you can light a lot of subject pretty inexpensively. You can buy smallish foam core cards at Target for about $2.50 each.

Get a couple of hot lights for table top photography. You can pick up a set of 500W quartz work lights from any home improvement store for about $40.

The down side is that those lights throw off some heat so you will be limited in the amount of time you can work with food. The solution is to use stand in food. If you are photographing a cake, get a second cake to use as model so you can dial in the exposure and focus. Then when you are ready to shoot, switch it out to the good one and fire away.

Even delicate foods like cheesecake and ice cream will still last 30 seconds to several minutes under hot lights.