If you have the few extra bucks to invest do as other users suggested and buy and resell on ebay. For example computer games are easy to sell and there is always some promo.
Also if you are good at skateboarding you should definitely do a blog(tumblr,blogger,wordpress) or if you are willing to spend couple of extra bucks buy hosting + domain and start working on it. In the long run this will definitely bring you some profit, since I assume you are passionate about skateboarding and it will be a lot easier to create interesting content and make it appealing to the visitors.
Also the good thing about skateboarding is that you can make quite a few bucks with selling shirts,board or anything related to skareboarding. Be creative
Most people can't take action and that's the only reason they aren't making money. I have tried countless methods and absolutely each one of them has made me some $$. You just have to find what you are most suited for.