I know the tax deadline has passed, but I figured I'd chime in with my experience since I had quite a bit of trouble with this. This is US based. Tapas does not send you a 1099, which my novel contact confirmed. I found this strange, but I'm not exactly an expert on types of employers, freelance work, and requirements in sending out 1099s. I earned over $600, so I had to report. Even if you earn less than $600, you are legally required to report all income. It's true the government would have a hard time discovering you got the money, but it could lead to consequences should it indeed be discovered you didn't report it.
Going on, my contact told me that Paypal would actually have a 1099 available for me. Unfortunately, because the requirements for self-reported income changed and caused confusion, it led to a mandated delay that meant Paypal didn't have send out the 1099s. So, there I was--technically having to follow the new guidelines while screwed out of the paperwork I needed to file my Tapas income. I had to use the Schedule C form instead, which should generally be what you use if you earn less than $600. It was incredibly confusing, but I managed to get it in. I ended up having to pay on my federal return and a local form because this was the first year I'd had any income like this and wasn't sure how to withhold what I needed.
Taxes are fun.
(Although, hopefully the new changes coming to the IRS and filing system will make things easier down the line.)