I am constantly getting asked about how to put together a speedlight (small flash) based light setup on a budget. You can get a solid two light set up for under $240 (single light for near $150). It may lack some of the bells and whistles, but it will be a reliable setup.
Before we get to my recommendations, here are a few caveats:
1. All of the items I mention are buying new. You can find some good deals on used gear on ebay or craigslist.
2. In an effort to save time, and simplify the purchasing process, all products come from two places: the Meking eBay store, and B & H Photo.
3. These are not necessarily products I use, but they are products I am familiar with. I have, over time, added to, and sold off various components of my small flash setup. For example, I started off with Cactus wireless triggers, then I found a deal on PocketWizard Plus II transceivers, and more recently settled on the JrX Studio from Radiopopper. I will probably switch again.
4. I don't use my small flash set up for every shoot I do.