There are different ways to find some online work. For example, you should look into work at home sites from people that update their site on a consistent basis. You can sometimes find writing work on there from people who offers free job listings for people that are looking for one. It never hurt to use some of them if you’re subscribing to them. I do writing, blogging and review work so I use those sites very often.
Since I do freelance work, I go on those sites every single week. As for doing promotions, I check up on some of the Facebook groups that cater to my promo gigs.
Simplyhired.com is a good site to use but only if you live in the US. I would sometimes use it to search for promotional work in conjunction to Facebook and Craigslist.