Hi Kristi.
As someone who manages advertising for several clients, what we've been doing (in addition to using SB ads directly) is:
1) Google Ads - Depending on what you're trying to accomplish (goals) - the recommendation would be different, but Google ads include display ads (like what you get on SB), Search, and Shopping Ads.
2) Facebook Ads - Facebook ads are a good value and highly targeted to whatever targets are identified. Identifying the right targets is key. (this includes Instagram)
It's very easy to fall into some traps (whether or not Google and/or Facebook intend for them to be traps) that can easily deplete your budget very quickly.
With one recent client, who was a "Google Ad - DIY'er" - he came to us to make some tweaks to his existing AdWords campaigns. After just a few short days, his typical bounce rate from his ads went from almost 90% down to around 50%. According to the dive shop, his business picked up almost immediately, and with gusto.
Radio, Print, and TV are very expensive for a small business, and rarely are as targeted as using at the very least the 2 aforementioned outlets.