Since I wanted to enter the Share Your Garden Photo Contest, and it is still about 2 weeks before it's safe to plant outside where I live, I'm showing my living room seed starting setup. Here are pepper plants and tomato plants that I started in mid-April. The desk lamps are on a timer so that they are on for about 16 hours each day. I potted up the tomatoes when they got their first true leaves. Peppers, on the far left, have only gotten their cotyledons so far, which don't do much for the mature plant. When the next set of leaves start to come on, I'll put them in bigger pots.
Starting seedlings indoors during the cold weather is a great way to save money and provides a sign of hope that warm weather just may be on its way! The whole project, seeds + seed starting medium, cost about $10. I already had the desk lamps laying around, so I'm not counting the cost of those. Cost of energy is a factor, but I'm just blissfully ignoring that for now.
The key to this type of setup is lots of light and not too much water. Window light alone is not sufficient where I live, even though is looks bright outside. Too much water and you risk dampening off, a condition that causes yellowing and plant death. Also, seed starting medium, which is very fine soil with a little vermiculite, is key to seed growth. Potting soil may contain sticks and rocks and other things that don't give a seedling much of a chance of pushing through.
Try starting your own seeds indoors instead of shelling out cash at the nursery - saves money and is pretty fun!