YouTube is a great place to find lots and lots of counting songs and videos...
YouTube also has a TON of super quick Sesame Street video segments. It doesn't take too much time to incorporate these videos into your math instruction. Sesame Street has video podcasts available on iTunes. I used these a lot last year. They are a bit longer (about 6-7 minutes) and are organized by numbers all the way up to 20 AND its totally free!
These two books are class favorites. The children easily memorize the songs, which makes them easy to "read". Song books are always a big hit in any kindergarten classroom. A song book basket is a great addition to your classroom library too!
I like to use these guided readers in lessons too. The text is very simple and its an easy way for teachers to get out math manips to practice counting and showing the number. The kids love following along with the book and "matching the number".
Finally, five frames are a great visual for our little learners. Donna at Math Coach's Corner has a little summary of how to address the Common Core Standards using five frames and dot cards. Here are some five frame freebies from Multi-Grade Matters. Thanks Deborah for sharing!