I would start with a piece of art over the sofa. That will get a color scheme going for you from which you can pull the colors for pillows. Here's a possibility but this company offers many more at a very reasonable price. http://www.gallerydirect.com/art/product/william-ireland/blue-boats?substrate_id=2&product_style_id=5&frame_id=10&size=18x15

I'd add an Ikea floor lamp at the far end of the sectional and a small table lamp on the bar ledge in the kitchen. The small table lamp could be a chrome office lamp from Ikea. Is there an Ikea near you?

You really need a coffee table, but it won't fit into the budget unless you find something on Craigslist.