There are so many questions I still have regarding the marketing of my books and I know I'm not alone. I can't even tell you how many articles, blogs and author sites I've read and done research on. I'm compiling information and hoping to have some helpful information for me and for you, but meanwhile I will give you this little (huge) tidbit. www.fiverr.com.
If you are self publishing you may be on a bit of a budget and if you need marketing material, be it physical or electronic, you need to peruse their list of talent. Everything starts at $5.
Now due to my academic background I was able to create my own book cover and this lovely banner for my facebook and twitter accounts, but I got a 3-D version of my cover on fiverr in 4 styles for $10. Money in my pocket.