I've also had a difficult time hiring lately. Usually a problem I always have when sales are good.
One thing that works well for me in recruiting, as someone who needs to rely on mostly high-school and college aged kids, is offering an extremely flexible schedule. My turnover is way below the industry average. I pay decent enough (for my industry) but not top dollar. However, my employees basically write their own schedules and very rarely do they get denied any request for a day off. They love the flexibility and it keeps them around.
Also I've discovered that I get a lot more applications in when I run a "now hiring" promoted post on Facebook versus things like Craigslist or newspaper ads. Last hiring Facebook promoted post I ran cost $100, got me 15,000 views including almost 100 shares, plus another 50 or so comments which were basically people tagging any of their friends who they knew were job hunting. Managed to get 8 new hires out of that versus trying Craigslist just before running that promoted post and getting nothing.