1. List stuff on Ebay. It's a lot easier than people think. Follow the steps to list your item - ebay leads you through the process. Tips: Take a good photo - outside gives best light. People want to see what they are buying so make sure the picture is clear and well lit. For shipping it really helps to have a postal scale so you can have ebay calculate and charge the shipping for you. If you don't have a scale consider doing the flat rate shipping box from the post office. Here is a place that sells scales.
2. Got any broken gold or silver jewlery laying around? Mis-matched earrings, ugly stuff you hate and never wear? Sell them to the local pawn shop or jewlery store. It's easy. Go to two places to get a quote and sell to the highest offer.
3. Have a garage sale. Price stuff to sell and when you are done load the leftovers into your car and straight to Goodwill. This will make you a couple bucks and also declutter your house. Win Win!
4. Are you a decent writer? You can make money by writing articles for textbroker.com. They don't pay a lot - a penny a word for a 3 star author, but it's real money and nothing to sniff at.
5. Have an unusual skill? Try creating a listing on fiverr.com where people list things they will do for 5 dollars.